:Product: 0419RSGA.txt :Issued: 2018 Apr 19 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 109 Issued at 2200Z on 19 Apr 2018 IA. Analysis of Solar Active Regions and Activity from 18/2100Z to 19/2100Z: Solar activity has been at very low levels for the past 24 hours. There is currently 1 numbered sunspot region 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 (20 Apr, 21 Apr, 22 Apr). IIA. Geophysical Activity Summary 18/2100Z to 19/2100Z: The geomagnetic field has been at quiet levels for the past 24 hours. Solar wind speed reached a peak of 302 km/s at 19/0231Z. Electrons greater than 2 MeV at geosynchronous orbit reached a peak level of 1782 pfu. IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be at quiet to active levels on days one and two (20 Apr, 21 Apr) and quiet to unsettled levels on day three (22 Apr). III. Event probabilities 20 Apr-22 Apr Class M 01/01/01 Class X 01/01/01 Proton 01/01/01 PCAF green IV. Penticton 10.7 cm Flux Observed 19 Apr 071 Predicted 20 Apr-22 Apr 072/072/072 90 Day Mean 19 Apr 070 V. Geomagnetic A Indices Observed Afr/Ap 18 Apr 006/006 Estimated Afr/Ap 19 Apr 005/006 Predicted Afr/Ap 20 Apr-22 Apr 011/015-011/012-007/008 VI. Geomagnetic Activity Probabilities 20 Apr-22 Apr A. Middle Latitudes Active 35/30/25 Minor Storm 20/10/05 Major-severe storm 05/01/01 B. High Latitudes Active 15/15/20 Minor Storm 30/30/30 Major-severe storm 45/35/25