:Product: 20011119RSGA.txt :Issued: 2001 Nov 19 2200 UTC # Prepared jointly by the U.S. Dept. of Commerce, NOAA, # Space Environment Center and the U.S. Air Force. # Joint USAF/NOAA Report of Solar and Geophysical Activity SDF Number 323 Issued at 2200Z on 19 Nov 2001 IA. Analysis of Solar Active Regions and Activity from 18/2100Z to 19/2100Z: Solar activity was low. Region 9704 (S18E02) produced a number of C-class subflares, the largest being a C4/Sf at 19/0701 UTC. This Region remains the most magnetically complex presently on the disk. IB. Solar Activity Forecast: Solar activity is expected to be low to moderate. Region 9704 remains capable of M-class flares. IIA. Geophysical Activity Summary 18/2100Z to 19/2100Z: The geomagnetic field ranged from quiet to active levels. A shock was observed at the NASA ACE spacecraft at about 19/1735 UTC, followed by a sudden impulse at ground magnetometers (10 nT at Boulder) at about 19/1815 UTC. This shock is believed to be associated with a CME which occurred on 17 November. The greater than 10 MeV proton flux at geosynchronous orbit exceeded the 10 pfu event threshold at 19/1230 UTC. This event remains in progress with a maximum flux so far of 20 pfu at 19/2055 UTC. This event is believed to also be associated with the M2/1n/CME event on 17 November. IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be unsettled to active for the next 24 hours becoming quiet to unsettled by the end of the three day forecast period. The greater than 10 MeV proton event is expected to end within the next 48 hours. III. Event Probabilities 20 Nov-22 Nov Class M 50/50/50 Class X 10/10/10 Proton 95/50/10 PCAF yellow IV. Penticton 10.7 cm Flux Observed 19 Nov 191 Predicted 20 Nov-22 Nov 190/185/180 90 Day Mean 19 Nov 218 V. Geomagnetic A Indices Observed Afr/Ap 18 Nov 008/007 Estimated Afr/Ap 19 Nov 015/015 Predicted Afr/Ap 20 Nov-22 Nov 015/015-010/012-010/012 VI. Geomagnetic Activity Probabilities 20 Nov-22 Nov A. Middle Latitudes Active 25/20/20 Minor storm 10/05/05 Major-severe storm 05/01/01 B. High Latitudes Active 25/25/25 Minor storm 10/10/10 Major-severe storm 05/05/05