:Product: 1226RSGA.txt :Issued: 2017 Dec 26 2200 UTC # Prepared jointly by the U.S. Dept. of Commerce, NOAA, # Space Weather Prediction Center and the U.S. Air Force. # Joint USAF/NOAA Solar Geophysical Activity Report and Forecast SDF Number 360 Issued at 2200Z on 26 Dec 2017 IA. Analysis of Solar Active Regions and Activity from 25/2100Z to 26/2100Z: 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 (27 Dec, 28 Dec, 29 Dec). IIA. Geophysical Activity Summary 25/2100Z to 26/2100Z: The geomagnetic field has been at quiet to unsettled levels for the past 24 hours. Solar wind speed reached a peak of 484 km/s at 26/1945Z. Total IMF reached 8 nT at 25/2105Z. The maximum southward component of Bz reached -5 nT at 25/2146Z. Electrons greater than 2 MeV at geosynchronous orbit reached a peak level of 704 pfu. IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be at quiet to active levels on day one (27 Dec), quiet to unsettled levels on day two (28 Dec) and quiet levels on day three (29 Dec). III. Event probabilities 27 Dec-29 Dec Class M 01/01/01 Class X 01/01/01 Proton 01/01/01 PCAF green IV. Penticton 10.7 cm Flux Observed 26 Dec 072 Predicted 27 Dec-29 Dec 072/072/071 90 Day Mean 26 Dec 074 V. Geomagnetic A Indices Observed Afr/Ap 25 Dec 009/008 Estimated Afr/Ap 26 Dec 010/012 Predicted Afr/Ap 27 Dec-29 Dec 010/008-007/006-005/005 VI. Geomagnetic Activity Probabilities 27 Dec-29 Dec A. Middle Latitudes Active 30/10/10 Minor Storm 05/05/01 Major-severe storm 01/01/01 B. High Latitudes Active 20/20/15 Minor Storm 25/20/15 Major-severe storm 20/15/10