:Product: 0417RSGA.txt :Issued: 2018 Apr 17 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 107 Issued at 2200Z on 17 Apr 2018 IA. Analysis of Solar Active Regions and Activity from 16/2100Z to 17/2100Z: 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 (18 Apr, 19 Apr, 20 Apr). IIA. Geophysical Activity Summary 16/2100Z to 17/2100Z: The geomagnetic field has been at quiet levels for the past 24 hours. Solar wind speed reached a peak of 487 km/s at 17/0757Z. Electrons greater than 2 MeV at geosynchronous orbit reached a peak level of 4585 pfu. IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be at quiet to unsettled levels on days one and three (18 Apr, 20 Apr) and quiet to active levels on day two (19 Apr). III. Event probabilities 18 Apr-20 Apr Class M 01/01/01 Class X 01/01/01 Proton 01/01/01 PCAF green IV. Penticton 10.7 cm Flux Observed 17 Apr 069 Predicted 18 Apr-20 Apr 070/070/070 90 Day Mean 17 Apr 070 V. Geomagnetic A Indices Observed Afr/Ap 16 Apr 003/002 Estimated Afr/Ap 17 Apr 004/005 Predicted Afr/Ap 18 Apr-20 Apr 007/008-008/012-007/010 VI. Geomagnetic Activity Probabilities 18 Apr-20 Apr A. Middle Latitudes Active 10/35/30 Minor Storm 01/20/10 Major-severe storm 01/05/01 B. High Latitudes Active 20/15/15 Minor Storm 20/30/30 Major-severe storm 10/45/35