:Product: 0516RSGA.txt :Issued: 2016 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 137 Issued at 2200Z on 16 May 2016 IA. Analysis of Solar Active Regions and Activity from 15/2100Z to 16/2100Z: Solar activity has been at low levels for the past 24 hours. The largest solar event of the period was a C1 event observed at 16/1525Z from Region 2544 (N20W27). There are currently 5 numbered sunspot regions on the disk. IB. Solar Activity Forecast: Solar activity is likely to be low with a slight chance for an M-class flare on day one (17 May) and likely to be low on days two and three (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 567 km/s at 16/0113Z. Total IMF reached 8 nT at 16/1636Z. The maximum southward component of Bz reached -7 nT at 16/1154Z. Protons greater than 10 MeV at geosynchronous orbit reached a peak level of 2 pfu at 15/2315Z. Electrons greater than 2 MeV at geosynchronous orbit reached a peak level of 1269 pfu. IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be at quiet to active levels on days one and three (17 May, 19 May) and quiet to unsettled levels on day two (18 May). III. Event probabilities 17 May-19 May Class M 10/05/05 Class X 01/01/01 Proton 01/01/01 PCAF green IV. Penticton 10.7 cm Flux Observed 16 May 102 Predicted 17 May-19 May 102/100/100 90 Day Mean 16 May 093 V. Geomagnetic A Indices Observed Afr/Ap 15 May 012/013 Estimated Afr/Ap 16 May 015/019 Predicted Afr/Ap 17 May-19 May 010/012-008/008-014/018 VI. Geomagnetic Activity Probabilities 17 May-19 May A. Middle Latitudes Active 30/25/35 Minor Storm 15/05/20 Major-severe storm 05/01/05 B. High Latitudes Active 10/15/10 Minor Storm 30/30/25 Major-severe storm 50/30/50