:Product: 0131RSGA.txt :Issued: 2013 Jan 31 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 31 Issued at 2200Z on 31 Jan 2013 IA. Analysis of Solar Active Regions and Activity from 30/2100Z to 31/2100Z: 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 31/0434Z from Region 1663 (S09W24). There are currently 4 numbered sunspot regions on the disk. IB. Solar Activity Forecast: Solar activity is expected to be very low with a chance for C-class flares on days one, two, and three (01 Feb, 02 Feb, 03 Feb). IIA. Geophysical Activity Summary 30/2100Z to 31/2100Z: The geomagnetic field has been at quiet levels for the past 24 hours. Solar wind speed, as measured by the ACE spacecraft, reached a peak speed of 344 km/s at 31/2011Z. Total IMF reached 6.5 nT at 31/2045Z. The maximum southward component of Bz reached -4.4 nT at 31/2023Z. Electrons greater than 2 MeV at geosynchronous orbit reached a peak level of 367 pfu. IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be at quiet to active levels on day one (01 Feb) increasing to unsettled to active levels on days two and three (02 Feb, 03 Feb) as a coronal hole high speed stream becomes geoeffective and is, followed by a glancing blow from an earth-directed CME. III. Event probabilities 01 Feb-03 Feb Class M 01/01/01 Class X 01/01/01 Proton 01/01/01 PCAF green IV. Penticton 10.7 cm Flux Observed 31 Jan 103 Predicted 01 Feb-03 Feb 100/105/105 90 Day Mean 31 Jan 119 V. Geomagnetic A Indices Observed Afr/Ap 30 Jan 002/001 Estimated Afr/Ap 31 Jan 002/002 Predicted Afr/Ap 01 Feb-03 Feb 005/005-007/012-012/018 VI. Geomagnetic Activity Probabilities 01 Feb-03 Feb A. Middle Latitudes Active 10/10/25 Minor Storm 01/01/10 Major-severe storm 01/01/01 B. High Latitudes Active 15/15/15 Minor Storm 15/20/25 Major-severe storm 10/10/35