:Product: 1220RSGA.txt :Issued: 2018 Dec 20 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 354 Issued at 2200Z on 20 Dec 2018 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 0 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 650 km/s at 20/0741Z. Total IMF reached 7 nT at 20/0430Z. The maximum southward component of Bz reached -6 nT at 20/0512Z. Electrons greater than 2 MeV at geosynchronous orbit reached a peak level of 184 pfu. IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be at quiet to unsettled levels on day one (21 Dec) and quiet 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 070 Predicted 21 Dec-23 Dec 070/070/070 90 Day Mean 20 Dec 069 V. Geomagnetic A Indices Observed Afr/Ap 19 Dec 004/004 Estimated Afr/Ap 20 Dec 010/011 Predicted Afr/Ap 21 Dec-23 Dec 007/008-006/005-006/005 VI. Geomagnetic Activity Probabilities 21 Dec-23 Dec A. Middle Latitudes Active 10/10/15 Minor Storm 05/01/01 Major-severe storm 01/01/01 B. High Latitudes Active 15/15/20 Minor Storm 15/15/20 Major-severe storm 15/15/10