Joint USAF/NOAA Solar Geophysical Activity Report and Forecast SDF Number 137 Issued at 2200Z on 17 May 2017
IA. Analysis of Solar Active Regions and Activity from 16/2100Z to 17/2100Z: Solar activity has been at very low levels for the past 24 hours. There are currently 1 numbered sunspot regions on the disk. IB. Solar Activity Forecast: Solar activity is expected to be very low with a slight chance for a C-class flare on days one, two, and three (18 May, 19 May, 20 May).
IIA. Geophysical Activity Summary 16/2100Z to 17/2100Z: The geomagnetic field has been at quiet to unsettled levels for the past 24 hours. Solar wind speed reached a peak of 561 km/s at 16/2146Z. Total IMF reached 6 nT at 17/0855Z. The maximum southward component of Bz reached -5 nT at 17/0913Z. Electrons greater than 2 MeV at geosynchronous orbit reached a peak level of 256 pfu. IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be at quiet to minor storm levels on day one (18 May), active to major storm levels on day two (19 May) and active to minor storm levels on day three (20 May).
III. Event probabilities 18 May-20 May Class M 01/01/01 Class X 01/01/01 Proton 01/01/01 PCAF green
IV. Penticton 10.7 cm Flux Observed 17 May 071 Predicted 18 May-20 May 071/071/071 90 Day Mean 17 May 077
V. Geomagnetic A Indices Observed Afr/Ap 16 May 010/008 Estimated Afr/Ap 17 May 012/014 Predicted Afr/Ap 18 May-20 May 015/020-031/045-024/030
VI. Geomagnetic Activity Probabilities 18 May-20 May A. Middle Latitudes Active 35/30/40 Minor Storm 20/35/20 Major-severe storm 05/15/01 B. High Latitudes Active 15/15/15 Minor Storm 15/20/20 Major-severe storm 10/20/15