:Product: 0526RSGA.txt :Issued: 2017 May 26 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 146 Issued at 2200Z on 26 May 2017 IA. Analysis of Solar Active Regions and Activity from 25/2100Z to 26/2100Z: Solar activity has been at very low levels for the past 24 hours. There are currently 1 numbered sunspot regions on the disk. IB. Solar Activity Forecast: Solar activity is expected to be very low with a chance for a C-class flares on days one, two, and three (27 May, 28 May, 29 May). IIA. Geophysical Activity Summary 25/2100Z to 26/2100Z: The geomagnetic field has been at quiet levels for the past 24 hours. Solar wind speed reached a peak of 816 km/s at 26/0143Z. Electrons greater than 2 MeV at geosynchronous orbit reached a peak level of 13744 pfu. IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be at unsettled to active levels on day one (27 May), quiet to unsettled levels on day two (28 May) and quiet levels on day three (29 May). III. Event probabilities 27 May-29 May Class M 05/05/05 Class X 01/01/01 Proton 01/01/01 PCAF green IV. Penticton 10.7 cm Flux Observed 26 May 080 Predicted 27 May-29 May 080/075/070 90 Day Mean 26 May 076 V. Geomagnetic A Indices Observed Afr/Ap 25 May 004/004 Estimated Afr/Ap 26 May 008/011 Predicted Afr/Ap 27 May-29 May 015/020-008/010-006/005 VI. Geomagnetic Activity Probabilities 27 May-29 May A. Middle Latitudes Active 20/15/10 Minor Storm 05/05/01 Major-severe storm 01/01/01 B. High Latitudes Active 15/15/15 Minor Storm 20/20/15 Major-severe storm 15/20/10