:Product: 0318RSGA.txt :Issued: 2013 Mar 18 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 77 Issued at 2200Z on 18 Mar 2013 IA. Analysis of Solar Active Regions and Activity from 17/2100Z to 18/2100Z: Solar activity has been at low levels for the past 24 hours. The largest solar event of the period was a C2 event observed at 18/0321Z from Region 1698 (S19W86). There are currently 6 numbered sunspot regions on the disk. IB. Solar Activity Forecast: Solar activity is expected to be low with a slight chance for an M-class flare on days one and two (19 Mar, 20 Mar) and expected to be very low with a chance for a C-class flares and a slight chance for an M-class flare on day three (21 Mar). IIA. Geophysical Activity Summary 17/2100Z to 18/2100Z: The geomagnetic field has been at quiet to minor storm levels for the past 24 hours. Solar wind speed, as measured by the ACE spacecraft, reached a peak speed of 702 km/s at 18/0049Z. Total IMF reached 11 nT at 17/2106Z. The maximum southward component of Bz reached -5 nT at 17/2112Z. Protons greater than 10 MeV at geosynchronous orbit reached a peak level of 2 pfu at 17/2105Z. Electrons greater than 2 MeV at geosynchronous orbit reached a peak level of 253 pfu. IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be at quiet to unsettled levels on days one and two (19 Mar, 20 Mar) and quiet to active levels on day three (21 Mar). III. Event probabilities 19 Mar-21 Mar Class M 20/10/10 Class X 01/01/01 Proton 01/01/01 PCAF green IV. Penticton 10.7 cm Flux Observed 18 Mar 118 Predicted 19 Mar-21 Mar 115/110/105 90 Day Mean 18 Mar 116 V. Geomagnetic A Indices Observed Afr/Ap 17 Mar 032/057 Estimated Afr/Ap 18 Mar 010/011 Predicted Afr/Ap 19 Mar-21 Mar 009/008-008/008-008/010 VI. Geomagnetic Activity Probabilities 19 Mar-21 Mar A. Middle Latitudes Active 15/15/25 Minor Storm 05/05/05 Major-severe storm 01/01/01 B. High Latitudes Active 15/15/15 Minor Storm 20/20/30 Major-severe storm 20/20/30