:Product: 0516RSGA.txt :Issued: 2017 May 16 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 136 Issued at 2200Z on 16 May 2017 IA. Analysis of Solar Active Regions and Activity from 15/2100Z to 16/2100Z: 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 (17 May, 18 May, 19 May). IIA. Geophysical Activity Summary 15/2100Z to 16/2100Z: The geomagnetic field has been at quiet to unsettled levels for the past 24 hours. Solar wind speed reached a peak of 678 km/s at 16/0601Z. Total IMF reached 7 nT at 15/2305Z. The maximum southward component of Bz reached -4 nT at 15/2112Z. Electrons greater than 2 MeV at geosynchronous orbit reached a peak level of 112 pfu. IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be at active to major storm levels on days one, two, and three (17 May, 18 May, 19 May). III. Event probabilities 17 May-19 May Class M 01/01/01 Class X 01/01/01 Proton 01/01/01 PCAF green IV. Penticton 10.7 cm Flux Observed 16 May 072 Predicted 17 May-19 May 072/072/072 90 Day Mean 16 May 077 V. Geomagnetic A Indices Observed Afr/Ap 15 May 017/010 Estimated Afr/Ap 16 May 011/015 Predicted Afr/Ap 17 May-19 May 021/030-021/030-033/050 VI. Geomagnetic Activity Probabilities 17 May-19 May A. Middle Latitudes Active 35/35/30 Minor Storm 40/40/40 Major-severe storm 15/15/15 B. High Latitudes Active 15/15/15 Minor Storm 20/20/20 Major-severe storm 20/20/30