Activity was at low levels today. Region 790 (S10W93) produced the largest flare during the period, a very impulsive C4 flare which occurred at 17/0629Z. This region also produced multiple B-class flares as it began rotating beyond the solar west limb. Spotless Region 789 (N17W86) was responsible for producing several B-class flares today. A back-sided full halo CME, which is believed to be from old Region 786 (N12 L=056), was first observed on LASCO C2 imagery at 17/1130Z. No new regions were numbered today.

Solar activity is expected to be at very low to low levels.

The geomagnetic field ranged from quiet to minor storm levels. A weak transient signature (likely from the X1 related CME activity seen on 14 July) was detected at the ACE spacecraft near 17/0000Z where the wind speeds increased from near 425 km/sec to 500 km/sec. Minor storming was later observed between 17/0900 and 1200Z. The greater than 10 MeV proton event that began on 14/0245Z, had a peak flux of 134 pfu at 15/0345Z, and underwent an injection of flux at 17/1735Z allowing for the event to remain in-progress at near 17 pfu at the time of this writing. The source believed responsible for the increase in proton flux was the back-sided activity relating to the full halo CME mentioned in 1A.

The geomagnetic field is expected to be at predominantly quiet to unsettled levels on 18 and 19 July. A recurrent high speed coronal hole stream is expected to become geoeffective 20 July with active to minor storming expected and isolated major storm conditions possible. The greater than 10 proton event is expected to end on 18 July.

  Geobserveerd       17 Jul 074
  Voorspeld   18 Jul-20 Jul  075/075/075
  90 dagen gemiddelde        17 Jul 097

  Geobserveerd Afr/Ap 16 Jul  010/009
  Geraamd     Afr/Ap 17 Jul  010/020
  Voorspeld    Afr/Ap 18 Jul-20 Jul  005/015-008/012-020/025