Joint USAF/NOAA Solar Geophysical Activity Report and Forecast SDF Number 111 Issued at 2200Z on 21 Apr 2017
IA. Analysis of Solar Active Regions and Activity from 20/2100Z to 21/2100Z: Solar activity has been at very low levels for the past 24 hours. There are currently 3 numbered sunspot regions on the disk. IB. Solar Activity Forecast: Solar activity is expected to be very low with a chance for a C-class flares on days one, two, and three (22 Apr, 23 Apr, 24 Apr).
IIA. Geophysical Activity Summary 20/2100Z to 21/2100Z: The geomagnetic field has been at quiet to minor storm levels for the past 24 hours. Solar wind speed reached a peak of 691 km/s at 21/2050Z. Total IMF reached 14 nT at 21/1613Z. The maximum southward component of Bz reached -12 nT at 21/1635Z. Electrons greater than 2 MeV at geosynchronous orbit reached a peak level of 2805 pfu. IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be at quiet to unsettled levels on day one (22 Apr), active to major storm levels on day two (23 Apr) and active to minor storm levels on day three (24 Apr).
III. Event probabilities 22 Apr-24 Apr Class M 05/05/05 Class X 01/01/01 Proton 01/01/01 PCAF green
IV. Penticton 10.7 cm Flux Observed 21 Apr 082 Predicted 22 Apr-24 Apr 082/082/082 90 Day Mean 21 Apr 078
V. Geomagnetic A Indices Observed Afr/Ap 20 Apr 020/030 Estimated Afr/Ap 21 Apr 012/018 Predicted Afr/Ap 22 Apr-24 Apr 013/015-028/040-023/030
VI. Geomagnetic Activity Probabilities 22 Apr-24 Apr A. Middle Latitudes Active 40/30/40 Minor Storm 25/40/30 Major-severe storm 05/15/05 B. High Latitudes Active 10/05/05 Minor Storm 25/20/20 Major-severe storm 60/75/65