:Product: 0318RSGA.txt :Issued: 2025 Mar 18 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 77 Issued at 2200Z on 18 Mar 2025 IA. Analysis of Solar Active Regions and Activity from 17/2100Z to 18/2100Z: Solar activity has been at low levels for the past 24 hours. There are currently 13 numbered sunspot regions on the disk. IB. Solar Activity Forecast: Solar activity is expected to be low with a chance for M-class flares and a slight chance for an X-class flare on days one, two, and three (19 Mar, 20 Mar, 21 Mar). IIA. Geophysical Activity Summary 17/2100Z to 18/2100Z: The geomagnetic field has been at quiet to unsettled levels for the past 24 hours. Solar wind speed reached a peak of 480 km/s at 18/1810Z. Total IMF reached 10 nT at 18/2057Z. The maximum southward component of Bz reached -7 nT at 18/1223Z. Electrons greater than 2 MeV at geosynchronous orbit reached a peak level of 3091 pfu. IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be at quiet to active levels on days one and two (19 Mar, 20 Mar) and quiet to unsettled levels on day three (21 Mar). III. Event probabilities 19 Mar-21 Mar Class M 50/50/50 Class X 10/10/10 Proton 05/05/05 PCAF green IV. Penticton 10.7 cm Flux Observed 18 Mar 184 Predicted 19 Mar-21 Mar 185/185/190 90 Day Mean 18 Mar 189 V. Geomagnetic A Indices Observed Afr/Ap 17 Mar 014/014 Estimated Afr/Ap 18 Mar 012/015 Predicted Afr/Ap 19 Mar-21 Mar 010/012-011/012-007/008 VI. Geomagnetic Activity Probabilities 19 Mar-21 Mar A. Middle Latitudes Active 30/30/20 Minor Storm 10/10/05 Major-severe storm 01/01/01 B. High Latitudes Active 15/15/15 Minor Storm 30/30/30 Major-severe storm 40/40/30