Joint USAF/NOAA Solar Geophysical Activity Report and Forecast SDF Number 354 Issued at 2200Z on 20 Dec 2017
IA. Analysis of Solar Active Regions and Activity from 19/2100Z to 20/2100Z: 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 on days one, two, and three (21 Dec, 22 Dec, 23 Dec).
IIA. Geophysical Activity Summary 19/2100Z to 20/2100Z: The geomagnetic field has been at quiet to unsettled levels for the past 24 hours. Solar wind speed reached a peak of 505 km/s at 19/2200Z. Electrons greater than 2 MeV at geosynchronous orbit reached a peak level of 4134 pfu. IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be at quiet levels on day one (21 Dec) and quiet to unsettled levels on days two and three (22 Dec, 23 Dec).
III. Event probabilities 21 Dec-23 Dec Class M 01/01/01 Class X 01/01/01 Proton 01/01/01 PCAF green
IV. Penticton 10.7 cm Flux Observed 20 Dec 074 Predicted 21 Dec-23 Dec 075/075/075 90 Day Mean 20 Dec 075
V. Geomagnetic A Indices Observed Afr/Ap 19 Dec 004/003 Estimated Afr/Ap 20 Dec 006/006 Predicted Afr/Ap 21 Dec-23 Dec 005/005-007/008-008/008
VI. Geomagnetic Activity Probabilities 21 Dec-23 Dec A. Middle Latitudes Active 10/20/20 Minor Storm 01/05/05 Major-severe storm 01/01/01 B. High Latitudes Active 15/15/20 Minor Storm 20/30/30 Major-severe storm 10/30/25