Joint USAF/NOAA Solar Geophysical Activity Report and Forecast 13 May 2013
Joint USAF/NOAA Solar Geophysical Activity Report and Forecast SDF Number 133 Issued at 2200Z on 13 May 2013 IA. Analysis of Solar Active Regions and Activity from 12/2100Z to 13/2100Z: Solar activity has been at high levels for the past 24 hours. The largest solar event of the period was a X2 event observed at 13/1605Z from Region 1748(N12E86). There are currently 9 numbered sunspot regions on the disk. IB. Solar Activity Forecast: Solar activity is expected to be moderate with a chance for X-class flares on days one, two, and three (14 May, 15 May, 16 May). IIA. Geophysical Activity Summary 12/2100Z to 13/2100Z: The geomagnetic field has been at quiet to unsettled levels for the past 24 hours. Solar wind speed, as measured by the ACE spacecraft, reached a peak speed of 395 km/s at 13/0623Z. Total IMF reached 7 nT at 13/1650Z. The maximum southward component of Bz reached -6 nT at 13/0514Z. Electrons greater than 2 MeV at geosynchronous orbit reached a peak level of 501 pfu. IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be at quiet levels on day one (14 May), quiet to active levels on day two (15 May) and quiet to unsettled levels on day three (16 May). Protons have a slight chance of crossing threshold on days one, two, and three (14 May, 15 May, 16 May). III. Event probabilities 14 May-16 May Class M 80/80/80 Class X 40/40/40 Proton 20/20/20 PCAF green IV. Penticton 10.7 cm Flux Observed 13 May 150 Predicted 14 May-16 May 150/150/145 90 Day Mean 13 May 118 V. Geomagnetic A Indices Observed Afr/Ap 12 May 006/005 Estimated Afr/Ap 13 May 006/006 Predicted Afr/Ap 14 May-16 May 003/005-010/015-006/008 VI. Geomagnetic Activity Probabilities 14 May-16 May A. Middle Latitudes Active 10/25/15 Minor Storm 01/05/05 Major-severe storm 01/01/01 B. High Latitudes Active 15/15/15 Minor Storm 15/30/25 Major-severe storm 10/30/25
