:Product: 0121RSGA.txt :Issued: 2017 Jan 21 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 21 Issued at 2200Z on 21 Jan 2017 IA. Analysis of Solar Active Regions and Activity from 20/2100Z to 21/2100Z: Solar activity has been at low levels for the past 24 hours. The largest solar event of the period was a C9 event observed at 21/0726Z from Region 2628 (N12E36). There are currently 4 numbered sunspot regions on the disk. IB. Solar Activity Forecast: Solar activity is likely to be low with a chance for M-class flares on days one, two, and three (22 Jan, 23 Jan, 24 Jan). IIA. Geophysical Activity Summary 20/2100Z to 21/2100Z: The geomagnetic field has been at quiet to unsettled levels for the past 24 hours. Solar wind speed reached a peak of 536 km/s at 20/2126Z. Total IMF reached 6 nT at 21/1541Z. The maximum southward component of Bz reached -4 nT at 21/0512Z. Electrons greater than 2 MeV at geosynchronous orbit reached a peak level of 2839 pfu. IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be at quiet to unsettled levels on day one (22 Jan) and quiet levels on days two and three (23 Jan, 24 Jan). III. Event probabilities 22 Jan-24 Jan Class M 25/25/25 Class X 01/01/01 Proton 01/01/01 PCAF green IV. Penticton 10.7 cm Flux Observed 21 Jan 086 Predicted 22 Jan-24 Jan 085/085/082 90 Day Mean 21 Jan 077 V. Geomagnetic A Indices Observed Afr/Ap 20 Jan 009/007 Estimated Afr/Ap 21 Jan 007/009 Predicted Afr/Ap 22 Jan-24 Jan 007/008-006/005-006/005 VI. Geomagnetic Activity Probabilities 22 Jan-24 Jan A. Middle Latitudes Active 10/05/05 Minor Storm 01/01/01 Major-severe storm 01/01/01 B. High Latitudes Active 20/15/15 Minor Storm 25/20/20 Major-severe storm 15/10/10