:Product: 0527RSGA.txt :Issued: 2018 May 27 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 147 Issued at 2200Z on 27 May 2018 IA. Analysis of Solar Active Regions and Activity from 26/2100Z to 27/2100Z: Solar activity has been at very low levels for the past 24 hours. There are currently 2 numbered sunspot regions 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 (28 May, 29 May, 30 May). IIA. Geophysical Activity Summary 26/2100Z to 27/2100Z: The geomagnetic field has been at quiet levels for the past 24 hours. Solar wind speed reached a peak of 376 km/s at 27/2003Z. Total IMF reached 6 nT at 27/1808Z. The maximum southward component of Bz reached -3 nT at 27/1000Z. Electrons greater than 2 MeV at geosynchronous orbit reached a peak level of 320 pfu. IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be at quiet to unsettled levels on days one and two (28 May, 29 May) and quiet levels on day three (30 May). III. Event probabilities 28 May-30 May Class M 01/01/01 Class X 01/01/01 Proton 01/01/01 PCAF green IV. Penticton 10.7 cm Flux Observed 27 May 075 Predicted 28 May-30 May 073/072/072 90 Day Mean 27 May 070 V. Geomagnetic A Indices Observed Afr/Ap 26 May 005/003 Estimated Afr/Ap 27 May 005/005 Predicted Afr/Ap 28 May-30 May 008/008-008/008-005/005 VI. Geomagnetic Activity Probabilities 28 May-30 May A. Middle Latitudes Active 15/15/05 Minor Storm 05/05/01 Major-severe storm 01/01/01 B. High Latitudes Active 15/15/15 Minor Storm 25/25/15 Major-severe storm 25/25/05