Avvisi e Osservazioni del SWPC della NOAA

Il Centro di Predizione Meteorologico Spaziale dell'Amministrazione Atmosferica e Oceanica Nazionale (SWPC della NOAA) è l'agenzia governativa meteorologica spaziale ufficiale degli Stati Uniti che fornisce allerte e avvisi per i disturbi meteorologici spaziali. Sotto troverete le ultime allerte e avvisi meteorologici spaziali emessi dal SWPC della NOAA.

giovedì, 21 maggio AM

05:09 UTC

Space Weather Message Code: ALTEF3
Serial Number: 3691
Issue Time: 2026 May 21 0509 UTC

CONTINUED ALERT: Electron 2MeV Integral Flux exceeded 1000pfu
Continuation of Serial Number: 3690
Begin Time: 2026-05-16 17:40
Yesterday Maximum 2MeV Flux: 1717 pfu
Continued 2026-05-21 05:07 by Forecaster User

Continued 2026-05-21 05:07 by Forecaster User

mercoledì, 20 maggio AM

10:06 UTC

Space Weather Message Code: ALTEF3
Serial Number: 3690
Issue Time: 2026 May 20 1006 UTC

CONTINUED ALERT: Electron 2MeV Integral Flux exceeded 1000pfu
Continuation of Serial Number: 3689
Begin Time: 2026-05-16 17:40
Yesterday Maximum 2MeV Flux: 2860 pfu
Continued 2026-05-20 10:06 by Forecaster User

Continued 2026-05-20 10:06 by Forecaster User

martedì, 19 maggio PM

23:56 UTC

Space Weather Message Code: WARK04
Serial Number: 5346
Issue Time: 2026 May 19 2356 UTC

EXTENDED WARNING: Geomagnetic K-index of 4 expected
Extension to Serial Number: 5345
Valid From: 2026-05-19T07:01:00
Now Valid Until: 2026-05-20 06:00
Warning Condition: Persistence
Extended 2026-05-19 23:56 by Forecaster User

Extended 2026-05-19 23:56 by Forecaster User

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact primarily poleward of 65 degrees Geomagnetic Latitude.
Induced Currents - Weak power grid fluctuations can occur.
Aurora - Aurora may be visible at high latitudes such as Canada and Alaska.

20:57 UTC

Space Weather Message Code: WARK04
Serial Number: 5345
Issue Time: 2026 May 19 2057 UTC

EXTENDED WARNING: Geomagnetic K-index of 4 expected
Extension to Serial Number: 5344
Valid From: 2026-05-19T07:01:00
Now Valid Until: 2026-05-19 24:00
Warning Condition: Persistence
Extended 2026-05-19 20:57 by Forecaster User

Extended 2026-05-19 20:57 by Forecaster User

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact primarily poleward of 65 degrees Geomagnetic Latitude.
Induced Currents - Weak power grid fluctuations can occur.
Aurora - Aurora may be visible at high latitudes such as Canada and Alaska.

16:42 UTC

Space Weather Message Code: WARK04
Serial Number: 5344
Issue Time: 2026 May 19 1642 UTC

EXTENDED WARNING: Geomagnetic K-index of 4 expected
Extension to Serial Number: 5343
Valid From: 2026-05-19T07:01:00
Now Valid Until: 2026-05-19 21:00
Warning Condition: Persistence
Extended 2026-05-19 16:41 by Forecaster User

Extended 2026-05-19 16:41 by Forecaster User

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact primarily poleward of 65 degrees Geomagnetic Latitude.
Induced Currents - Weak power grid fluctuations can occur.
Aurora - Aurora may be visible at high latitudes such as Canada and Alaska.

08:55 UTC

Space Weather Message Code: ALTK04
Serial Number: 2657
Issue Time: 2026 May 19 0855 UTC

ALERT: Geomagnetic K-index of 4
Threshold Reached: 2026 May 19 0828 UTC
Synoptic Period: 0600-0900
Active Warning: YES
Comment:



NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact primarily poleward of 65 degrees Geomagnetic Latitude.
Induced Currents - Weak power grid fluctuations can occur.
Aurora - Aurora may be visible at high latitudes such as Canada and Alaska.

07:03 UTC

Space Weather Message Code: WARK04
Serial Number: 5343
Issue Time: 2026 May 19 0703 UTC

WARNING: Geomagnetic K-index of 4 expected
Valid From: 2026 May 19 0701 UTC
Valid To: 2026 May 19 1800 UTC
Warning Conditions: Onset
Comment:



NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact primarily poleward of 65 degrees Geomagnetic Latitude.
Induced Currents - Weak power grid fluctuations can occur.
Aurora - Aurora may be visible at high latitudes such as Canada and Alaska.

05:14 UTC

Space Weather Message Code: ALTEF3
Serial Number: 3689
Issue Time: 2026 May 19 0514 UTC

ALERT: Electron 2MeV Integral Flux exceeded 1000pfu
Threshold Reached: 2026 May 16 1740 UTC
Station: GOES-19
Comment: Yesterday's max: 6667 pfu


Yesterday's max: 6667 pfu

04:56 UTC

Space Weather Message Code: ALTEF3
Serial Number: 3689
Issue Time: 2026 May 19 0456 UTC

CONTINUED ALERT: Electron 2MeV Integral Flux exceeded 1000pfu
Continuation of Serial Number: 3688
Begin Time: 2026-05-16 17:40
Yesterday Maximum 2MeV Flux: 6118 pfu
Continued 2026-05-19 05:00 by Forecaster User

Continued 2026-05-19 05:00 by Forecaster User

lunedì, 18 maggio AM

05:00 UTC

Space Weather Message Code: ALTEF3
Serial Number: 3688
Issue Time: 2026 May 18 0500 UTC

CONTINUED ALERT: Electron 2MeV Integral Flux exceeded 1000pfu
Continuation of Serial Number: 3687
Begin Time: 2026-05-16 17:40
Yesterday Maximum 2MeV Flux: 6118 pfu
Continued 2026-05-18 04:59 by Forecaster User

Continued 2026-05-18 04:59 by Forecaster User

domenica, 17 maggio PM

21:16 UTC

Space Weather Message Code: SUM10R
Serial Number: 913
Issue Time: 2026 May 17 2116 UTC

SUMMARY: 10cm Radio Burst
Begin Time: 2026 May 17 2050 UTC
Maximum Time: 2026 May 17 2051 UTC
End Time: 2026 May 17 2051 UTC
Peak Flux: 370 sfu
Duration: 1 minutes
Latest Penticton Noon Flux: 104 sfu
Comment:

16:12 UTC

Space Weather Message Code: WATA20
Serial Number: 1113
Issue Time: 2026 May 17 1612 UTC

WATCH: Geomagnetic Storm Category G1 Predicted
Highest Storm Level Predicted by Day:
May 18: G1 (Minor) May 19: G1 (Minor) May 20: None (Below G1)
THIS SUPERSEDES ANY/ALL PRIOR WATCHES IN EFFECT
Comment:



NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact primarily poleward of 60 degrees Geomagnetic Latitude.
Induced Currents - Weak power grid fluctuations can occur.
Spacecraft - Minor impact on satellite operations possible.
Aurora - Aurora may be visible at high latitudes, i.e., northern tier of the U.S. such as northern Michigan and Maine.

08:40 UTC

Space Weather Message Code: WARK04
Serial Number: 5342
Issue Time: 2026 May 17 0840 UTC

EXTENDED WARNING: Geomagnetic K-index of 4 expected
Extension to Serial Number: 5341
Valid From: 2026-05-13T20:26:00
Now Valid Until: 2026-05-17 21:00
Warning Condition: Persistence
Extended 2026-05-17 08:38 by Forecaster User

Extended 2026-05-17 08:38 by Forecaster User

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact primarily poleward of 65 degrees Geomagnetic Latitude.
Induced Currents - Weak power grid fluctuations can occur.
Aurora - Aurora may be visible at high latitudes such as Canada and Alaska.

08:16 UTC

Space Weather Message Code: ALTEF3
Serial Number: 3687
Issue Time: 2026 May 17 0816 UTC

CONTINUED ALERT: Electron 2MeV Integral Flux exceeded 1000pfu
Continuation of Serial Number: 3686
Begin Time: 2026-05-16 17:40
Yesterday Maximum 2MeV Flux: 1902 pfu
Continued 2026-05-17 08:16 by Forecaster User

Continued 2026-05-17 08:16 by Forecaster User

sabato, 16 maggio PM

21:34 UTC

Space Weather Message Code: WATA20
Serial Number: 1112
Issue Time: 2026 May 16 2134 UTC

WATCH: Geomagnetic Storm Category G1 Predicted
Highest Storm Level Predicted by Day:
May 17: G1 (Minor) May 18: G1 (Minor) May 19: None (Below G1)
THIS SUPERSEDES ANY/ALL PRIOR WATCHES IN EFFECT
Comment:



NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact primarily poleward of 60 degrees Geomagnetic Latitude.
Induced Currents - Weak power grid fluctuations can occur.
Spacecraft - Minor impact on satellite operations possible.
Aurora - Aurora may be visible at high latitudes, i.e., northern tier of the U.S. such as northern Michigan and Maine.

18:14 UTC

Space Weather Message Code: WARK05
Serial Number: 2237
Issue Time: 2026 May 16 1814 UTC

EXTENDED WARNING: Geomagnetic K-index of 5 expected
Extension to Serial Number: 2236
Valid From: 2026-05-15T13:05:00
Now Valid Until: 2026-05-17 09:00
Warning Condition: Persistence
Extended 2026-05-16 18:13 by WC

Extended 2026-05-16 18:13 by WC NOAA Scale: G1 - Minor

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact primarily poleward of 60 degrees Geomagnetic Latitude.
Induced Currents - Weak power grid fluctuations can occur.
Spacecraft - Minor impact on satellite operations possible.
Aurora - Aurora may be visible at high latitudes, i.e., northern tier of the U.S. such as northern Michigan and Maine.

18:13 UTC

Space Weather Message Code: WARK04
Serial Number: 5341
Issue Time: 2026 May 16 1813 UTC

EXTENDED WARNING: Geomagnetic K-index of 4 expected
Extension to Serial Number: 5340
Valid From: 2026-05-13T20:26:00
Now Valid Until: 2026-05-17 09:00
Warning Condition: Persistence
Extended 2026-05-16 18:12 by WC

Extended 2026-05-16 18:12 by WC

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact primarily poleward of 65 degrees Geomagnetic Latitude.
Induced Currents - Weak power grid fluctuations can occur.
Aurora - Aurora may be visible at high latitudes such as Canada and Alaska.

18:04 UTC

Space Weather Message Code: ALTK05
Serial Number: 2022
Issue Time: 2026 May 16 1804 UTC

ALERT: Geomagnetic K-index of 5
Threshold Reached: 2026 May 16 1759 UTC
Synoptic Period: 1500-1800
Active Warning: YES
Noaa Scale: G1 - Minor
Comment:

NOAA Scale: G1 - Minor

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact primarily poleward of 60 degrees Geomagnetic Latitude.
Induced Currents - Weak power grid fluctuations can occur.
Spacecraft - Minor impact on satellite operations possible.
Aurora - Aurora may be visible at high latitudes, i.e., northern tier of the U.S. such as northern Michigan and Maine.

17:53 UTC

Space Weather Message Code: ALTEF3
Serial Number: 3686
Issue Time: 2026 May 16 1753 UTC

ALERT: Electron 2MeV Integral Flux exceeded 1000pfu
Threshold Reached: 2026 May 16 1740 UTC
Station: GOES-19
Comment:

16:58 UTC

Space Weather Message Code: ALTTP4
Serial Number: 709
Issue Time: 2026 May 16 1658 UTC

ALERT: Type IV Radio Emission
Begin Time: 2026 May 16 1605 UTC
Comment:

16:37 UTC

Space Weather Message Code: SUM10R
Serial Number: 912
Issue Time: 2026 May 16 1637 UTC

SUMMARY: 10cm Radio Burst
Begin Time: 2026 May 16 1606 UTC
Maximum Time: 2026 May 16 1609 UTC
End Time: 2026 May 16 1610 UTC
Peak Flux: 170 sfu
Duration: 4 minutes
Latest Penticton Noon Flux: 101 sfu
Comment: COR for end date.


COR for end date.

16:31 UTC

Space Weather Message Code: SUM10R
Serial Number: 912
Issue Time: 2026 May 16 1631 UTC

SUMMARY: 10cm Radio Burst
Begin Time: 2026 May 16 1606 UTC
Maximum Time: 2026 May 16 1609 UTC
End Time: 2026 May 17 1610 UTC
Peak Flux: 170 sfu
Duration: 4 minutes
Latest Penticton Noon Flux: 101 sfu
Comment:

11:56 UTC

Space Weather Message Code: WARK04
Serial Number: 5340
Issue Time: 2026 May 16 1156 UTC

EXTENDED WARNING: Geomagnetic K-index of 4 expected
Extension to Serial Number: 5339
Valid From: 2026-05-13T20:26:00
Now Valid Until: 2026-05-16 23:59
Warning Condition: Persistence
Extended 2026-05-16 11:55 by Forecaster User

Extended 2026-05-16 11:55 by Forecaster User

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact primarily poleward of 65 degrees Geomagnetic Latitude.
Induced Currents - Weak power grid fluctuations can occur.
Aurora - Aurora may be visible at high latitudes such as Canada and Alaska.

08:59 UTC

Space Weather Message Code: ALTK05
Serial Number: 2021
Issue Time: 2026 May 16 0859 UTC

ALERT: Geomagnetic K-index of 5
Threshold Reached: 2026 May 16 0859 UTC
Synoptic Period: 0600-0900
Active Warning: YES
Noaa Scale: G1 - Minor
Comment:

NOAA Scale: G1 - Minor

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact primarily poleward of 60 degrees Geomagnetic Latitude.
Induced Currents - Weak power grid fluctuations can occur.
Spacecraft - Minor impact on satellite operations possible.
Aurora - Aurora may be visible at high latitudes, i.e., northern tier of the U.S. such as northern Michigan and Maine.

08:45 UTC

Space Weather Message Code: WARK05
Serial Number: 2236
Issue Time: 2026 May 16 0845 UTC

EXTENDED WARNING: Geomagnetic K-index of 5 expected
Extension to Serial Number: 2235
Valid From: 2026-05-15T13:05:00
Now Valid Until: 2026-05-16 21:00
Warning Condition: Persistence
Extended 2026-05-16 08:44 by Forecaster User

Extended 2026-05-16 08:44 by Forecaster User NOAA Scale: G1 - Minor

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact primarily poleward of 60 degrees Geomagnetic Latitude.
Induced Currents - Weak power grid fluctuations can occur.
Spacecraft - Minor impact on satellite operations possible.
Aurora - Aurora may be visible at high latitudes, i.e., northern tier of the U.S. such as northern Michigan and Maine.

05:56 UTC

Space Weather Message Code: ALTK05
Serial Number: 2020
Issue Time: 2026 May 16 0556 UTC

ALERT: Geomagnetic K-index of 5
Threshold Reached: 2026 May 16 0554 UTC
Synoptic Period: 0300-0600
Active Warning: YES
Noaa Scale: G1 - Minor
Comment:

NOAA Scale: G1 - Minor

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact primarily poleward of 60 degrees Geomagnetic Latitude.
Induced Currents - Weak power grid fluctuations can occur.
Spacecraft - Minor impact on satellite operations possible.
Aurora - Aurora may be visible at high latitudes, i.e., northern tier of the U.S. such as northern Michigan and Maine.

venerdì, 15 maggio PM

23:56 UTC

Space Weather Message Code: WARK05
Serial Number: 2235
Issue Time: 2026 May 15 2356 UTC

EXTENDED WARNING: Geomagnetic K-index of 5 expected
Extension to Serial Number: 2234
Valid From: 2026-05-15T13:05:00
Now Valid Until: 2026-05-16 09:00
Warning Condition: Persistence
Extended 2026-05-15 23:55 by Forecaster User

Extended 2026-05-15 23:55 by Forecaster User NOAA Scale: G1 - Minor

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact primarily poleward of 60 degrees Geomagnetic Latitude.
Induced Currents - Weak power grid fluctuations can occur.
Spacecraft - Minor impact on satellite operations possible.
Aurora - Aurora may be visible at high latitudes, i.e., northern tier of the U.S. such as northern Michigan and Maine.

22:15 UTC

Space Weather Message Code: ALTK06
Serial Number: 717
Issue Time: 2026 May 15 2215 UTC

ALERT: Geomagnetic K-index of 6
Threshold Reached: 2026 May 15 2215 UTC
Synoptic Period: 2100-2400
Active Warning: YES
Noaa Scale: G2 - Moderate
Comment:

NOAA Scale: G2 - Moderate

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact primarily poleward of 55 degrees Geomagnetic Latitude.
Induced Currents - Power grid fluctuations can occur. High-latitude power systems may experience voltage alarms.
Spacecraft - Satellite orientation irregularities may occur; increased drag on low Earth-orbit satellites is possible.
Radio - HF (high frequency) radio propagation can fade at higher latitudes.
Aurora - Aurora may be seen as low as New York to Wisconsin to Washington state.

22:02 UTC

Space Weather Message Code: WARK06
Serial Number: 660
Issue Time: 2026 May 15 2202 UTC

WARNING: Geomagnetic K-index of 6 expected
Valid From: 2026 May 15 2201 UTC
Valid To: 2026 May 16 0300 UTC
Warning Conditions: Onset
Noaa Scale: G2 - Moderate
Comment:

NOAA Scale: G2 - Moderate

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact primarily poleward of 55 degrees Geomagnetic Latitude.
Induced Currents - Power grid fluctuations can occur. High-latitude power systems may experience voltage alarms.
Spacecraft - Satellite orientation irregularities may occur; increased drag on low Earth-orbit satellites is possible.
Radio - HF (high frequency) radio propagation can fade at higher latitudes.
Aurora - Aurora may be seen as low as New York to Wisconsin to Washington state.

17:18 UTC

Space Weather Message Code: ALTTP2
Serial Number: 1487
Issue Time: 2026 May 15 1718 UTC

ALERT: Type II Radio Emission
Begin Time: 2026 May 15 1616 UTC
Estimate Velocity: 529 km/s
Comment:

16:07 UTC

Space Weather Message Code: ALTK05
Serial Number: 2019
Issue Time: 2026 May 15 1607 UTC

ALERT: Geomagnetic K-index of 5
Threshold Reached: 2026 May 15 1606 UTC
Synoptic Period: 1500-1800
Active Warning: YES
Noaa Scale: G1 - Minor
Comment:

NOAA Scale: G1 - Minor

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact primarily poleward of 60 degrees Geomagnetic Latitude.
Induced Currents - Weak power grid fluctuations can occur.
Spacecraft - Minor impact on satellite operations possible.
Aurora - Aurora may be visible at high latitudes, i.e., northern tier of the U.S. such as northern Michigan and Maine.

14:50 UTC

Space Weather Message Code: WARK06
Serial Number: 659
Issue Time: 2026 May 15 1450 UTC

WARNING: Geomagnetic K-index of 6 expected
Valid From: 2026 May 15 1449 UTC
Valid To: 2026 May 15 2100 UTC
Warning Conditions: Onset
Noaa Scale: G2 - Moderate
Comment:

NOAA Scale: G2 - Moderate

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact primarily poleward of 55 degrees Geomagnetic Latitude.
Induced Currents - Power grid fluctuations can occur. High-latitude power systems may experience voltage alarms.
Spacecraft - Satellite orientation irregularities may occur; increased drag on low Earth-orbit satellites is possible.
Radio - HF (high frequency) radio propagation can fade at higher latitudes.
Aurora - Aurora may be seen as low as New York to Wisconsin to Washington state.

13:45 UTC

Space Weather Message Code: ALTTP2
Serial Number: 1486
Issue Time: 2026 May 15 1345 UTC

ALERT: Type II Radio Emission
Begin Time: 2026 May 15 1344 UTC
Estimate Velocity: 347 km/s
Comment:

13:27 UTC

Space Weather Message Code: ALTK05
Serial Number: 2018
Issue Time: 2026 May 15 1327 UTC

ALERT: Geomagnetic K-index of 5
Threshold Reached: 2026 May 15 1326 UTC
Synoptic Period: 1200-1500
Active Warning: YES
Noaa Scale: G1 - Minor
Comment:

NOAA Scale: G1 - Minor

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact primarily poleward of 60 degrees Geomagnetic Latitude.
Induced Currents - Weak power grid fluctuations can occur.
Spacecraft - Minor impact on satellite operations possible.
Aurora - Aurora may be visible at high latitudes, i.e., northern tier of the U.S. such as northern Michigan and Maine.

13:12 UTC

Space Weather Message Code: WARK05
Serial Number: 2234
Issue Time: 2026 May 15 1307 UTC

WARNING: Geomagnetic K-index of 5 expected
Valid From: 2026 May 15 1305 UTC
Valid To: 2026 May 15 2359 UTC
Warning Conditions: Onset
Noaa Scale: G1 - Minor
Comment:

NOAA Scale: G1 - Minor

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact primarily poleward of 60 degrees Geomagnetic Latitude.
Induced Currents - Weak power grid fluctuations can occur.
Spacecraft - Minor impact on satellite operations possible.
Aurora - Aurora may be visible at high latitudes, i.e., northern tier of the U.S. such as northern Michigan and Maine.

13:09 UTC

Space Weather Message Code: WARK04
Serial Number: 5339
Issue Time: 2026 May 15 1309 UTC

EXTENDED WARNING: Geomagnetic K-index of 4 expected
Extension to Serial Number: 5337
Valid From: 2026-05-13T20:26:00
Now Valid Until: 2026-05-16 12:00
Warning Condition: Persistence
Extended 2026-05-15 13:09 by Forecaster User

Extended 2026-05-15 13:09 by Forecaster User

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact primarily poleward of 65 degrees Geomagnetic Latitude.
Induced Currents - Weak power grid fluctuations can occur.
Aurora - Aurora may be visible at high latitudes such as Canada and Alaska.

13:00 UTC

Space Weather Message Code: ALTK04
Serial Number: 2656
Issue Time: 2026 May 15 1300 UTC

ALERT: Geomagnetic K-index of 4
Threshold Reached: 2026 May 15 1300 UTC
Synoptic Period: 1200-1500
Active Warning: YES
Comment:



NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact primarily poleward of 65 degrees Geomagnetic Latitude.
Induced Currents - Weak power grid fluctuations can occur.
Aurora - Aurora may be visible at high latitudes such as Canada and Alaska.

12:25 UTC

Space Weather Message Code: ALTTP2
Serial Number: 1485
Issue Time: 2026 May 15 1225 UTC

ALERT: Type II Radio Emission
Begin Time: 2026 May 15 1225 UTC
Estimate Velocity: 486 km/s
Comment:

11:58 UTC

Space Weather Message Code: WARK04
Serial Number: 5338
Issue Time: 2026 May 15 1158 UTC

WARNING: Geomagnetic K-index of 4 expected
Valid From: 2026 May 15 1157 UTC
Valid To: 2026 May 16 0000 UTC
Warning Conditions: Onset
Comment:



NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact primarily poleward of 65 degrees Geomagnetic Latitude.
Induced Currents - Weak power grid fluctuations can occur.
Aurora - Aurora may be visible at high latitudes such as Canada and Alaska.

giovedì, 14 maggio AM

08:53 UTC

Space Weather Message Code: WATA30
Serial Number: 273
Issue Time: 2026 May 14 0853 UTC

WATCH: Geomagnetic Storm Category G2 Predicted
Highest Storm Level Predicted by Day:
May 15: G2 (Moderate) May 16: G1 (Minor) May 17: G1 (Minor)
THIS SUPERSEDES ANY/ALL PRIOR WATCHES IN EFFECT
Comment: included the G1 watch for day3 (17 May)


included the G1 watch for day3 (17 May)

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact primarily poleward of 55 degrees Geomagnetic Latitude.
Induced Currents - Power grid fluctuations can occur. High-latitude power systems may experience voltage alarms.
Spacecraft - Satellite orientation irregularities may occur; increased drag on low Earth-orbit satellites is possible.
Radio - HF (high frequency) radio propagation can fade at higher latitudes.
Aurora - Aurora may be seen as low as New York to Wisconsin to Washington state.

mercoledì, 13 maggio PM

20:27 UTC

Space Weather Message Code: WARK04
Serial Number: 5337
Issue Time: 2026 May 13 2027 UTC

WARNING: Geomagnetic K-index of 4 expected
Valid From: 2026 May 13 2026 UTC
Valid To: 2026 May 14 0600 UTC
Warning Conditions: Onset
Comment:



NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact primarily poleward of 65 degrees Geomagnetic Latitude.
Induced Currents - Weak power grid fluctuations can occur.
Aurora - Aurora may be visible at high latitudes such as Canada and Alaska.

09:07 UTC

Space Weather Message Code: WATA30
Serial Number: 273
Issue Time: 2026 May 13 0907 UTC

WATCH: Geomagnetic Storm Category G2 Predicted
Highest Storm Level Predicted by Day:
May 14: None (Below G1) May 15: G2 (Moderate) May 16: G1 (Minor)
THIS SUPERSEDES ANY/ALL PRIOR WATCHES IN EFFECT
Comment:



NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact primarily poleward of 55 degrees Geomagnetic Latitude.
Induced Currents - Power grid fluctuations can occur. High-latitude power systems may experience voltage alarms.
Spacecraft - Satellite orientation irregularities may occur; increased drag on low Earth-orbit satellites is possible.
Radio - HF (high frequency) radio propagation can fade at higher latitudes.
Aurora - Aurora may be seen as low as New York to Wisconsin to Washington state.

martedì, 12 maggio PM

13:26 UTC

Space Weather Message Code: WATA20
Serial Number: 1111
Issue Time: 2026 May 12 1326 UTC

WATCH: Geomagnetic Storm Category G1 Predicted
Highest Storm Level Predicted by Day:
May 13: None (Below G1) May 14: None (Below G1) May 15: G1 (Minor)
THIS SUPERSEDES ANY/ALL PRIOR WATCHES IN EFFECT
Comment: Negative CH influence


Negative CH influence

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact primarily poleward of 60 degrees Geomagnetic Latitude.
Induced Currents - Weak power grid fluctuations can occur.
Spacecraft - Minor impact on satellite operations possible.
Aurora - Aurora may be visible at high latitudes, i.e., northern tier of the U.S. such as northern Michigan and Maine.

domenica, 10 maggio PM

14:14 UTC

Space Weather Message Code: SUMXM5
Serial Number: 316
Issue Time: 2026 May 10 1414 UTC

SUMMARY: X-ray Event exceeded M5
Begin Time: 2026 May 10 1319 UTC
Maximum Time: 2026 May 10 1339 UTC
End Time: 2026 May 10 1402 UTC
Xray Class: M5.7
Optical Class:
Location: N18E65
Noaa Scale: R2 - Moderate
Comment:

NOAA Scale: R2 - Moderate

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact centered primarily on sub-solar point on the sunlit side of Earth.
Radio - Limited blackout of HF (high frequency) radio communication for tens of minutes.

13:55 UTC

Space Weather Message Code: SUM10R
Serial Number: 911
Issue Time: 2026 May 10 1355 UTC

SUMMARY: 10cm Radio Burst
Begin Time: 2026 May 10 1328 UTC
Maximum Time: 2026 May 10 1334 UTC
End Time: 2026 May 10 1343 UTC
Peak Flux: 550 sfu
Duration: 15 minutes
Latest Penticton Noon Flux: 122 sfu
Comment:

13:47 UTC

Space Weather Message Code: ALTTP2
Serial Number: 1484
Issue Time: 2026 May 10 1347 UTC

ALERT: Type II Radio Emission
Begin Time: 2026 May 10 1329 UTC
Estimate Velocity: 650 km/s
Comment:

13:38 UTC

Space Weather Message Code: ALTXMF
Serial Number: 528
Issue Time: 2026 May 10 1338 UTC

ALERT: X-Ray Flux exceeded M5
Threshold Reached: 2026 May 10 1335 UTC
Noaa Scale: R2 - Moderate
Comment:

NOAA Scale: R2 - Moderate

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact centered on sub-solar point on the sunlit side of Earth. Extent of blackout of HF (high frequency) radio communication dependent upon current X-ray Flux intensity. For real-time information on affected area and expected duration please see http://www.swpc.noaa.gov/products/d-region-absorption-predictions-d-rap.

venerdì, 8 maggio PM

17:25 UTC

Space Weather Message Code: WARK04
Serial Number: 5336
Issue Time: 2026 May 08 1725 UTC

WARNING: Geomagnetic K-index of 4 expected
Valid From: 2026 May 08 1724 UTC
Valid To: 2026 May 08 2359 UTC
Warning Conditions: Onset
Comment:



NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact primarily poleward of 65 degrees Geomagnetic Latitude.
Induced Currents - Weak power grid fluctuations can occur.
Aurora - Aurora may be visible at high latitudes such as Canada and Alaska.

giovedì, 7 maggio PM

16:37 UTC

Space Weather Message Code: WARK04
Serial Number: 5335
Issue Time: 2026 May 07 1637 UTC

WARNING: Geomagnetic K-index of 4 expected
Valid From: 2026 May 07 1635 UTC
Valid To: 2026 May 08 1500 UTC
Warning Condition: Onset

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact primarily poleward of 65 degrees Geomagnetic Latitude.
Induced Currents - Weak power grid fluctuations can occur.
Aurora - Aurora may be visible at high latitudes such as Canada and Alaska.

martedì, 5 maggio AM

02:49 UTC

Space Weather Message Code: ALTK05
Serial Number: 2016
Issue Time: 2026 May 05 0249 UTC

ALERT: Geomagnetic K-index of 5
Threshold Reached: 2026 May 05 0244 UTC
Synoptic Period: 0000-0300 UTC

Active Warning: Yes
NOAA Scale: G1 - Minor

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact primarily poleward of 60 degrees Geomagnetic Latitude.
Induced Currents - Weak power grid fluctuations can occur.
Spacecraft - Minor impact on satellite operations possible.
Aurora - Aurora may be visible at high latitudes, i.e., northern tier of the U.S. such as northern Michigan and Maine.

lunedì, 4 maggio PM

23:55 UTC

Space Weather Message Code: ALTK05
Serial Number: 2015
Issue Time: 2026 May 04 2355 UTC

ALERT: Geomagnetic K-index of 5
Threshold Reached: 2026 May 04 2355 UTC
Synoptic Period: 2100-2400 UTC

Active Warning: Yes
NOAA Scale: G1 - Minor

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact primarily poleward of 60 degrees Geomagnetic Latitude.
Induced Currents - Weak power grid fluctuations can occur.
Spacecraft - Minor impact on satellite operations possible.
Aurora - Aurora may be visible at high latitudes, i.e., northern tier of the U.S. such as northern Michigan and Maine.

23:39 UTC

Space Weather Message Code: WARK04
Serial Number: 5334
Issue Time: 2026 May 04 2339 UTC

EXTENDED WARNING: Geomagnetic K-index of 4 expected
Extension to Serial Number: 5333
Valid From: 2026 May 04 1645 UTC
Now Valid Until: 2026 May 05 1200 UTC
Warning Condition: Persistence

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact primarily poleward of 65 degrees Geomagnetic Latitude.
Induced Currents - Weak power grid fluctuations can occur.
Aurora - Aurora may be visible at high latitudes such as Canada and Alaska.

23:39 UTC

Space Weather Message Code: WARK05
Serial Number: 2232
Issue Time: 2026 May 04 2339 UTC

EXTENDED WARNING: Geomagnetic K-index of 5 expected
Extension to Serial Number: 2231
Valid From: 2026 May 04 1945 UTC
Now Valid Until: 2026 May 05 0900 UTC
Warning Condition: Persistence

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact primarily poleward of 60 degrees Geomagnetic Latitude.
Induced Currents - Weak power grid fluctuations can occur.
Spacecraft - Minor impact on satellite operations possible.
Aurora - Aurora may be visible at high latitudes, i.e., northern tier of the U.S. such as northern Michigan and Maine.

23:39 UTC

Space Weather Message Code: WARK06
Serial Number: 657
Issue Time: 2026 May 04 2339 UTC

EXTENDED WARNING: Geomagnetic K-Index of 6 expected
Extension to Serial Number: 656
Valid From: 2026 May 04 2031 UTC
Now Valid Until: 2026 May 05 0600 UTC
Warning Condition: Persistence

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact primarily poleward of 55 degrees Geomagnetic Latitude.
Induced Currents - Power grid fluctuations can occur. High-latitude power systems may experience voltage alarms.
Spacecraft - Satellite orientation irregularities may occur; increased drag on low Earth-orbit satellites is possible.
Radio - HF (high frequency) radio propagation can fade at higher latitudes.
Aurora - Aurora may be seen as low as New York to Wisconsin to Washington state.

20:32 UTC

Space Weather Message Code: ALTK06
Serial Number: 715
Issue Time: 2026 May 04 2032 UTC

ALERT: Geomagnetic K-index of 6
Threshold Reached: 2026 May 04 2032 UTC
Synoptic Period: 1800-2100 UTC

Active Warning: Yes
NOAA Scale: G2 - Moderate

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact primarily poleward of 55 degrees Geomagnetic Latitude.
Induced Currents - Power grid fluctuations can occur. High-latitude power systems may experience voltage alarms.
Spacecraft - Satellite orientation irregularities may occur; increased drag on low Earth-orbit satellites is possible.
Radio - HF (high frequency) radio propagation can fade at higher latitudes.
Aurora - Aurora may be seen as low as New York to Wisconsin to Washington state.

20:31 UTC

Space Weather Message Code: WARK06
Serial Number: 656
Issue Time: 2026 May 04 2031 UTC

WARNING: Geomagnetic K-Index of 6 expected
Valid From: 2026 May 04 2031 UTC
Valid To: 2026 May 05 0000 UTC
Warning Condition: Onset
NOAA Scale: G2 - Moderate

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact primarily poleward of 55 degrees Geomagnetic Latitude.
Induced Currents - Power grid fluctuations can occur. High-latitude power systems may experience voltage alarms.
Spacecraft - Satellite orientation irregularities may occur; increased drag on low Earth-orbit satellites is possible.
Radio - HF (high frequency) radio propagation can fade at higher latitudes.
Aurora - Aurora may be seen as low as New York to Wisconsin to Washington state.

19:51 UTC

Space Weather Message Code: ALTK05
Serial Number: 2014
Issue Time: 2026 May 04 1951 UTC

ALERT: Geomagnetic K-index of 5
Threshold Reached: 2026 May 04 1951 UTC
Synoptic Period: 1800-2100 UTC

Active Warning: Yes
NOAA Scale: G1 - Minor

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact primarily poleward of 60 degrees Geomagnetic Latitude.
Induced Currents - Weak power grid fluctuations can occur.
Spacecraft - Minor impact on satellite operations possible.
Aurora - Aurora may be visible at high latitudes, i.e., northern tier of the U.S. such as northern Michigan and Maine.

19:50 UTC

Space Weather Message Code: WARK05
Serial Number: 2231
Issue Time: 2026 May 04 1950 UTC

WARNING: Geomagnetic K-index of 5 expected
Valid From: 2026 May 04 1945 UTC
Valid To: 2026 May 05 0000 UTC
Warning Condition: Onset
NOAA Scale: G1 - Minor

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact primarily poleward of 60 degrees Geomagnetic Latitude.
Induced Currents - Weak power grid fluctuations can occur.
Spacecraft - Minor impact on satellite operations possible.
Aurora - Aurora may be visible at high latitudes, i.e., northern tier of the U.S. such as northern Michigan and Maine.

16:49 UTC

Space Weather Message Code: ALTK04
Serial Number: 2654
Issue Time: 2026 May 04 1649 UTC

ALERT: Geomagnetic K-index of 4
Threshold Reached: 2026 May 04 1647 UTC
Synoptic Period: 1500-1800 UTC

Active Warning: Yes

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact primarily poleward of 65 degrees Geomagnetic Latitude.
Induced Currents - Weak power grid fluctuations can occur.
Aurora - Aurora may be visible at high latitudes such as Canada and Alaska.

16:49 UTC

Space Weather Message Code: WARK04
Serial Number: 5333
Issue Time: 2026 May 04 1649 UTC

WARNING: Geomagnetic K-index of 4 expected
Valid From: 2026 May 04 1645 UTC
Valid To: 2026 May 05 0300 UTC
Warning Condition: Onset

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact primarily poleward of 65 degrees Geomagnetic Latitude.
Induced Currents - Weak power grid fluctuations can occur.
Aurora - Aurora may be visible at high latitudes such as Canada and Alaska.

sabato, 2 maggio AM

11:11 UTC

Space Weather Message Code: ALTTP2
Serial Number: 1482
Issue Time: 2026 May 02 1111 UTC

ALERT: Type II Radio Emission
Begin Time: 2026 May 02 1051 UTC
Estimated Velocity: 641 km/s

Comment: Likely associated with C-class flare acitivity originating from AR 4420 on the west limb.



Description: Type II emissions occur in association with eruptions on the sun and typically indicate a coronal mass ejection is associated with a flare event.

venerdì, 1 maggio PM

15:50 UTC

Space Weather Message Code: ALTTP2
Serial Number: 1481
Issue Time: 2026 May 01 1550 UTC

ALERT: Type II Radio Emission
Begin Time: 2026 May 01 1535 UTC
Estimated Velocity: 593 km/s



Description: Type II emissions occur in association with eruptions on the sun and typically indicate a coronal mass ejection is associated with a flare event.

giovedì, 30 aprile PM

23:59 UTC

Space Weather Message Code: ALTK05
Serial Number: 2013
Issue Time: 2026 Apr 30 2359 UTC

ALERT: Geomagnetic K-index of 5
Threshold Reached: 2026 Apr 30 2359 UTC
Synoptic Period: 2100-2400 UTC

Active Warning: Yes
NOAA Scale: G1 - Minor

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact primarily poleward of 60 degrees Geomagnetic Latitude.
Induced Currents - Weak power grid fluctuations can occur.
Spacecraft - Minor impact on satellite operations possible.
Aurora - Aurora may be visible at high latitudes, i.e., northern tier of the U.S. such as northern Michigan and Maine.

23:11 UTC

Space Weather Message Code: WARK04
Serial Number: 5332
Issue Time: 2026 Apr 30 2311 UTC

EXTENDED WARNING: Geomagnetic K-index of 4 expected
Extension to Serial Number: 5331
Valid From: 2026 Apr 30 2005 UTC
Now Valid Until: 2026 May 01 1500 UTC
Warning Condition: Persistence

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact primarily poleward of 65 degrees Geomagnetic Latitude.
Induced Currents - Weak power grid fluctuations can occur.
Aurora - Aurora may be visible at high latitudes such as Canada and Alaska.

23:09 UTC

Space Weather Message Code: WARK05
Serial Number: 2230
Issue Time: 2026 Apr 30 2309 UTC

WARNING: Geomagnetic K-index of 5 expected
Valid From: 2026 Apr 30 2309 UTC
Valid To: 2026 May 01 0900 UTC
Warning Condition: Onset
NOAA Scale: G1 - Minor

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact primarily poleward of 60 degrees Geomagnetic Latitude.
Induced Currents - Weak power grid fluctuations can occur.
Spacecraft - Minor impact on satellite operations possible.
Aurora - Aurora may be visible at high latitudes, i.e., northern tier of the U.S. such as northern Michigan and Maine.

20:35 UTC

Space Weather Message Code: ALTK04
Serial Number: 2653
Issue Time: 2026 Apr 30 2035 UTC

ALERT: Geomagnetic K-index of 4
Threshold Reached: 2026 Apr 30 2035 UTC
Synoptic Period: 1800-2100 UTC

Active Warning: Yes

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact primarily poleward of 65 degrees Geomagnetic Latitude.
Induced Currents - Weak power grid fluctuations can occur.
Aurora - Aurora may be visible at high latitudes such as Canada and Alaska.

20:06 UTC

Space Weather Message Code: WARK04
Serial Number: 5331
Issue Time: 2026 Apr 30 2006 UTC

WARNING: Geomagnetic K-index of 4 expected
Valid From: 2026 Apr 30 2005 UTC
Valid To: 2026 May 01 0600 UTC
Warning Condition: Onset

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact primarily poleward of 65 degrees Geomagnetic Latitude.
Induced Currents - Weak power grid fluctuations can occur.
Aurora - Aurora may be visible at high latitudes such as Canada and Alaska.

lunedì, 27 aprile AM

01:06 UTC

Space Weather Message Code: ALTTP2
Serial Number: 1480
Issue Time: 2026 Apr 27 0106 UTC

ALERT: Type II Radio Emission
Begin Time: 2026 Apr 26 2257 UTC
Estimated Velocity: 834 km/s



Description: Type II emissions occur in association with eruptions on the sun and typically indicate a coronal mass ejection is associated with a flare event.

domenica, 26 aprile PM

23:33 UTC

Space Weather Message Code: WARK04
Serial Number: 5330
Issue Time: 2026 Apr 26 2333 UTC

EXTENDED WARNING: Geomagnetic K-index of 4 expected
Extension to Serial Number: 5329
Valid From: 2026 Apr 26 0359 UTC
Now Valid Until: 2026 Apr 27 0900 UTC
Warning Condition: Persistence

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact primarily poleward of 65 degrees Geomagnetic Latitude.
Induced Currents - Weak power grid fluctuations can occur.
Aurora - Aurora may be visible at high latitudes such as Canada and Alaska.

23:17 UTC

Space Weather Message Code: SUMXM5
Serial Number: 314
Issue Time: 2026 Apr 26 2317 UTC

SUMMARY: X-ray Event exceeded M5
Begin Time: 2026 Apr 26 2251 UTC
Maximum Time: 2026 Apr 26 2257 UTC
End Time: 2026 Apr 26 2302 UTC
X-ray Class: M6.0
Location: N21W33
NOAA Scale: R2 - Moderate

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact centered primarily on sub-solar point on the sunlit side of Earth.
Radio - Limited blackout of HF (high frequency) radio communication for tens of minutes.

23:08 UTC

Space Weather Message Code: SUM10R
Serial Number: 909
Issue Time: 2026 Apr 26 2308 UTC

SUMMARY: 10cm Radio Burst
Begin Time: 2026 Apr 26 2256 UTC
Maximum Time: 2026 Apr 26 2257 UTC
End Time: 2026 Apr 26 2258 UTC
Duration: 1 minutes
Peak Flux: 260 sfu
Latest Penticton Noon Flux: 148 sfu



Description: A 10cm radio burst indicates that the electromagnetic burst associated with a solar flare at the 10cm wavelength was double or greater than the initial 10cm radio background. This can be indicative of significant radio noise in association with a solar flare. This noise is generally short-lived but can cause interference for sensitive receivers including radar, GPS, and satellite communications.

23:00 UTC

Space Weather Message Code: ALTXMF
Serial Number: 526
Issue Time: 2026 Apr 26 2300 UTC

ALERT: X-Ray Flux exceeded M5
Threshold Reached: 2026 Apr 26 2257 UTC
NOAA Scale: R2 - Moderate

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact centered on sub-solar point on the sunlit side of Earth. Extent of blackout of HF (high frequency) radio communication dependent upon current X-ray Flux intensity. For real-time information on affected area and expected duration please see http://www.swpc.noaa.gov/products/d-region-absorption-predictions-d-rap.

11:47 UTC

Space Weather Message Code: WARK04
Serial Number: 5329
Issue Time: 2026 Apr 26 1147 UTC

EXTENDED WARNING: Geomagnetic K-index of 4 expected
Extension to Serial Number: 5328
Valid From: 2026 Apr 26 0359 UTC
Now Valid Until: 2026 Apr 26 2359 UTC
Warning Condition: Persistence

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact primarily poleward of 65 degrees Geomagnetic Latitude.
Induced Currents - Weak power grid fluctuations can occur.
Aurora - Aurora may be visible at high latitudes such as Canada and Alaska.

06:01 UTC

Space Weather Message Code: WARK04
Serial Number: 5328
Issue Time: 2026 Apr 26 0601 UTC

WARNING: Geomagnetic K-index of 4 expected
Valid From: 2026 Apr 26 0359 UTC
Valid To: 2026 Apr 26 1200 UTC
Warning Condition: Onset

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact primarily poleward of 65 degrees Geomagnetic Latitude.
Induced Currents - Weak power grid fluctuations can occur.
Aurora - Aurora may be visible at high latitudes such as Canada and Alaska.

05:59 UTC

Space Weather Message Code: ALTK04
Serial Number: 2652
Issue Time: 2026 Apr 26 0559 UTC

ALERT: Geomagnetic K-index of 4
Threshold Reached: 2026 Apr 26 0559 UTC
Synoptic Period: 0300-0600 UTC

Active Warning: Yes

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact primarily poleward of 65 degrees Geomagnetic Latitude.
Induced Currents - Weak power grid fluctuations can occur.
Aurora - Aurora may be visible at high latitudes such as Canada and Alaska.

sabato, 25 aprile AM

01:37 UTC

Space Weather Message Code: WARK04
Serial Number: 5327
Issue Time: 2026 Apr 25 0137 UTC

WARNING: Geomagnetic K-index of 4 expected
Valid From: 2026 Apr 25 0137 UTC
Valid To: 2026 Apr 25 2359 UTC
Warning Condition: Onset

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact primarily poleward of 65 degrees Geomagnetic Latitude.
Induced Currents - Weak power grid fluctuations can occur.
Aurora - Aurora may be visible at high latitudes such as Canada and Alaska.

venerdì, 24 aprile PM

23:50 UTC

Space Weather Message Code: WATA20
Serial Number: 1109
Issue Time: 2026 Apr 24 2350 UTC

WATCH: Geomagnetic Storm Category G1 Predicted

Highest Storm Level Predicted by Day:
Apr 25: G1 (Minor) Apr 26: G1 (Minor) Apr 27: None (Below G1)

THIS SUPERSEDES ANY/ALL PRIOR WATCHES IN EFFECT

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact primarily poleward of 60 degrees Geomagnetic Latitude.
Induced Currents - Weak power grid fluctuations can occur.
Spacecraft - Minor impact on satellite operations possible.
Aurora - Aurora may be visible at high latitudes, i.e., northern tier of the U.S. such as northern Michigan and Maine.

18:35 UTC

Space Weather Message Code: SUMXM5
Serial Number: 313
Issue Time: 2026 Apr 24 1835 UTC

SUMMARY: X-ray Event exceeded M5
Begin Time: 2026 Apr 24 1754 UTC
Maximum Time: 2026 Apr 24 1815 UTC
End Time: 2026 Apr 24 1830 UTC
X-ray Class: M6.4
Location: N19W90
NOAA Scale: R2 - Moderate

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact centered primarily on sub-solar point on the sunlit side of Earth.
Radio - Limited blackout of HF (high frequency) radio communication for tens of minutes.

18:12 UTC

Space Weather Message Code: ALTXMF
Serial Number: 525
Issue Time: 2026 Apr 24 1812 UTC

ALERT: X-Ray Flux exceeded M5
Threshold Reached: 2026 Apr 24 1812 UTC
NOAA Scale: R2 - Moderate

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact centered on sub-solar point on the sunlit side of Earth. Extent of blackout of HF (high frequency) radio communication dependent upon current X-ray Flux intensity. For real-time information on affected area and expected duration please see http://www.swpc.noaa.gov/products/d-region-absorption-predictions-d-rap.

10:42 UTC

Space Weather Message Code: ALTTP4
Serial Number: 707
Issue Time: 2026 Apr 24 1041 UTC

ALERT: Type IV Radio Emission
Begin Time: 2026 Apr 24 0840 UTC



Description: Type IV emissions occur in association with major eruptions on the sun and are typically associated with strong coronal mass ejections and solar radiation storms.

09:28 UTC

Space Weather Message Code: ALTTP2
Serial Number: 1479
Issue Time: 2026 Apr 24 0928 UTC

ALERT: Type II Radio Emission
Begin Time: 2026 Apr 24 0815 UTC
Estimated Velocity: 1293 km/s

Comment: Reissued with adjusted shock speed.



Description: Type II emissions occur in association with eruptions on the sun and typically indicate a coronal mass ejection is associated with a flare event.

09:27 UTC

Space Weather Message Code: ALTTP2
Serial Number: 1478
Issue Time: 2026 Apr 24 0927 UTC

CANCEL ALERT: Type II Radio Emission
Cancel Serial Number: 1477
Original Issue Time: 2026 Apr 24 0857 UTC

Comment: Reissuing with corrected shock speed.



Description: Type II emissions occur in association with eruptions on the sun and typically indicate a coronal mass ejection is associated with a flare event.

08:57 UTC

Space Weather Message Code: ALTTP2
Serial Number: 1477
Issue Time: 2026 Apr 24 0857 UTC

ALERT: Type II Radio Emission
Begin Time: 2026 Apr 24 0815 UTC
Estimated Velocity: 1869 km/s



Description: Type II emissions occur in association with eruptions on the sun and typically indicate a coronal mass ejection is associated with a flare event.

08:38 UTC

Space Weather Message Code: SUM10R
Serial Number: 908
Issue Time: 2026 Apr 24 0838 UTC

SUMMARY: 10cm Radio Burst
Begin Time: 2026 Apr 24 0809 UTC
Maximum Time: 2026 Apr 24 0811 UTC
End Time: 2026 Apr 24 0815 UTC
Duration: 6 minutes
Peak Flux: 570 sfu
Latest Penticton Noon Flux: 128 sfu



Description: A 10cm radio burst indicates that the electromagnetic burst associated with a solar flare at the 10cm wavelength was double or greater than the initial 10cm radio background. This can be indicative of significant radio noise in association with a solar flare. This noise is generally short-lived but can cause interference for sensitive receivers including radar, GPS, and satellite communications.

08:26 UTC

Space Weather Message Code: SUMX01
Serial Number: 216
Issue Time: 2026 Apr 24 0826 UTC

SUMMARY: X-ray Event exceeded X1
Begin Time: 2026 Apr 24 0801 UTC
Maximum Time: 2026 Apr 24 0813 UTC
End Time: 2026 Apr 24 0818 UTC
X-ray Class: X2.5
Optical Class: 2b
Location: N20W90
NOAA Scale: R3 - Strong

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact consists of large portions of the sunlit side of Earth, strongest at the sub-solar point.
Radio - Wide area blackout of HF (high frequency) radio communication for about an hour.

08:12 UTC

Space Weather Message Code: ALTXMF
Serial Number: 524
Issue Time: 2026 Apr 24 0812 UTC

ALERT: X-Ray Flux exceeded M5
Threshold Reached: 2026 Apr 24 0812 UTC
NOAA Scale: R2 - Moderate

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact centered on sub-solar point on the sunlit side of Earth. Extent of blackout of HF (high frequency) radio communication dependent upon current X-ray Flux intensity. For real-time information on affected area and expected duration please see http://www.swpc.noaa.gov/products/d-region-absorption-predictions-d-rap.

05:05 UTC

Space Weather Message Code: ALTEF3
Serial Number: 3684
Issue Time: 2026 Apr 24 0505 UTC

CONTINUED ALERT: Electron 2MeV Integral Flux exceeded 1000pfu
Continuation of Serial Number: 3683
Begin Time: 2026 Apr 19 1920 UTC
Yesterday Maximum 2MeV Flux: 3446 pfu



Potential Impacts: Satellite systems may experience significant charging resulting in increased risk to satellite systems.

01:31 UTC

Space Weather Message Code: SUMX01
Serial Number: 215
Issue Time: 2026 Apr 24 0131 UTC

SUMMARY: X-ray Event exceeded X1
Begin Time: 2026 Apr 24 0051 UTC
Maximum Time: 2026 Apr 24 0107 UTC
End Time: 2026 Apr 24 0113 UTC
X-ray Class: X2.4
Location: N17W71
NOAA Scale: R3 - Strong

Comment: Accompanied by a tenflare with a castelli-U signature. No radio observations currently available.

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact consists of large portions of the sunlit side of Earth, strongest at the sub-solar point.
Radio - Wide area blackout of HF (high frequency) radio communication for about an hour.

01:29 UTC

Space Weather Message Code: SUM10R
Serial Number: 907
Issue Time: 2026 Apr 24 0129 UTC

SUMMARY: 10cm Radio Burst
Begin Time: 2026 Apr 24 0103 UTC
Maximum Time: 2026 Apr 24 0104 UTC
End Time: 2026 Apr 24 0109 UTC
Duration: 6 minutes
Peak Flux: 570 sfu
Latest Penticton Noon Flux: 128 sfu



Description: A 10cm radio burst indicates that the electromagnetic burst associated with a solar flare at the 10cm wavelength was double or greater than the initial 10cm radio background. This can be indicative of significant radio noise in association with a solar flare. This noise is generally short-lived but can cause interference for sensitive receivers including radar, GPS, and satellite communications.

01:08 UTC

Space Weather Message Code: ALTXMF
Serial Number: 523
Issue Time: 2026 Apr 24 0108 UTC

ALERT: X-Ray Flux exceeded M5
Threshold Reached: 2026 Apr 24 0105 UTC
NOAA Scale: R2 - Moderate

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact centered on sub-solar point on the sunlit side of Earth. Extent of blackout of HF (high frequency) radio communication dependent upon current X-ray Flux intensity. For real-time information on affected area and expected duration please see http://www.swpc.noaa.gov/products/d-region-absorption-predictions-d-rap.

giovedì, 23 aprile PM

17:23 UTC

Space Weather Message Code: SUM10R
Serial Number: 906
Issue Time: 2026 Apr 23 1723 UTC

SUMMARY: 10cm Radio Burst
Begin Time: 2026 Apr 23 1703 UTC
Maximum Time: 2026 Apr 23 1705 UTC
End Time: 2026 Apr 23 1707 UTC
Duration: 4 minutes
Peak Flux: 220 sfu
Latest Penticton Noon Flux: 116 sfu



Description: A 10cm radio burst indicates that the electromagnetic burst associated with a solar flare at the 10cm wavelength was double or greater than the initial 10cm radio background. This can be indicative of significant radio noise in association with a solar flare. This noise is generally short-lived but can cause interference for sensitive receivers including radar, GPS, and satellite communications.

14:52 UTC

Space Weather Message Code: SUM10R
Serial Number: 905
Issue Time: 2026 Apr 23 1452 UTC

SUMMARY: 10cm Radio Burst
Begin Time: 2026 Apr 23 1355 UTC
Maximum Time: 2026 Apr 23 1356 UTC
End Time: 2026 Apr 23 1357 UTC
Duration: 2 minutes
Peak Flux: 170 sfu
Latest Penticton Noon Flux: 116 sfu



Description: A 10cm radio burst indicates that the electromagnetic burst associated with a solar flare at the 10cm wavelength was double or greater than the initial 10cm radio background. This can be indicative of significant radio noise in association with a solar flare. This noise is generally short-lived but can cause interference for sensitive receivers including radar, GPS, and satellite communications.

09:14 UTC

Space Weather Message Code: ALTTP2
Serial Number: 1476
Issue Time: 2026 Apr 23 0914 UTC

ALERT: Type II Radio Emission
Begin Time: 2026 Apr 23 0859 UTC
Estimated Velocity: 722 km/s

Comment: Report from San Vito



Description: Type II emissions occur in association with eruptions on the sun and typically indicate a coronal mass ejection is associated with a flare event.

08:59 UTC

Space Weather Message Code: SUM10R
Serial Number: 904
Issue Time: 2026 Apr 23 0859 UTC

SUMMARY: 10cm Radio Burst
Begin Time: 2026 Apr 23 0844 UTC
Maximum Time: 2026 Apr 23 0844 UTC
End Time: 2026 Apr 23 0844 UTC
Duration: 1 minutes
Peak Flux: 130 sfu
Latest Penticton Noon Flux: 116 sfu



Description: A 10cm radio burst indicates that the electromagnetic burst associated with a solar flare at the 10cm wavelength was double or greater than the initial 10cm radio background. This can be indicative of significant radio noise in association with a solar flare. This noise is generally short-lived but can cause interference for sensitive receivers including radar, GPS, and satellite communications.

05:35 UTC

Space Weather Message Code: ALTTP4
Serial Number: 706
Issue Time: 2026 Apr 23 0535 UTC

ALERT: Type IV Radio Emission
Begin Time: 2026 Apr 23 0513 UTC

Comment: Report from San Vito



Description: Type IV emissions occur in association with major eruptions on the sun and are typically associated with strong coronal mass ejections and solar radiation storms.

05:10 UTC

Space Weather Message Code: ALTTP2
Serial Number: 1475
Issue Time: 2026 Apr 23 0510 UTC

ALERT: Type II Radio Emission
Begin Time: 2026 Apr 23 0450 UTC
Estimated Velocity: 1033 km/s

Comment: Report from San Vito



Description: Type II emissions occur in association with eruptions on the sun and typically indicate a coronal mass ejection is associated with a flare event.

04:59 UTC

Space Weather Message Code: ALTEF3
Serial Number: 3683
Issue Time: 2026 Apr 23 0459 UTC

CONTINUED ALERT: Electron 2MeV Integral Flux exceeded 1000pfu
Continuation of Serial Number: 3682
Begin Time: 2026 Apr 19 1920 UTC
Yesterday Maximum 2MeV Flux: 4922 pfu



Potential Impacts: Satellite systems may experience significant charging resulting in increased risk to satellite systems.

mercoledì, 22 aprile AM

05:03 UTC

Space Weather Message Code: ALTEF3
Serial Number: 3682
Issue Time: 2026 Apr 22 0503 UTC

CONTINUED ALERT: Electron 2MeV Integral Flux exceeded 1000pfu
Continuation of Serial Number: 3681
Begin Time: 2026 Apr 19 1920 UTC
Yesterday Maximum 2MeV Flux: 4987 pfu



Potential Impacts: Satellite systems may experience significant charging resulting in increased risk to satellite systems.