:Product: 0419RSGA.txt :Issued: 2014 Apr 19 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 109 Issued at 2200Z on 19 Apr 2014 IA. Analysis of Solar Active Regions and Activity from 18/2100Z to 19/2100Z: Solar activity has been at low levels for the past 24 hours. The largest solar event of the period was a C4 event observed at 19/1932Z from Region 2032 (N12W83). There are currently 12 numbered sunspot regions on the disk. IB. Solar Activity Forecast: Solar activity is likely to be moderate with a slight chance for an X-class flare on day one (20 Apr) and expected to be low with a chance for M-class flares on days two and three (21 Apr, 22 Apr). IIA. Geophysical Activity Summary 18/2100Z to 19/2100Z: The geomagnetic field has been at quiet to active levels for the past 24 hours. Solar wind speed, as measured by the ACE spacecraft, reached a peak speed of 583 km/s at 19/1858Z. Total IMF reached 10 nT at 18/2118Z. The maximum southward component of Bz reached -6 nT at 18/2345Z. Protons greater than 10 MeV at geosynchronous orbit reached a peak level of 58 pfu at 19/0105Z. Electrons greater than 2 MeV at geosynchronous orbit reached a peak level of 242 pfu. IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be at unsettled to major storm levels on day one (20 Apr), quiet to minor storm levels on day two (21 Apr) and quiet to active levels on day three (22 Apr). Protons are expected to remain above the 10 pfu threshold on days one and two (20-21 Apr) and have a chance of crossing threshold on day three (22 Apr). III. Event probabilities 20 Apr-22 Apr Class M 55/50/50 Class X 10/05/05 Proton 99/75/50 PCAF red IV. Penticton 10.7 cm Flux Observed 19 Apr 169 Predicted 20 Apr-22 Apr 170/170/160 90 Day Mean 19 Apr 156 V. Geomagnetic A Indices Observed Afr/Ap 18 Apr 007/006 Estimated Afr/Ap 19 Apr 014/017 Predicted Afr/Ap 20 Apr-22 Apr 022/035-021/025-009/010 VI. Geomagnetic Activity Probabilities 20 Apr-22 Apr A. Middle Latitudes Active 30/40/35 Minor Storm 40/35/15 Major-severe storm 20/10/01 B. High Latitudes Active 05/05/10 Minor Storm 15/20/25 Major-severe storm 75/75/50