NOAA SEC Report of Solar-Geophysical Activity 23 Sep 2001
:Product: Report of Solar-Geophysical Activity :Issued: 2001 Sep 23 2200 UT # 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 266 Issued at 2200Z on 23 Sep 2001 IA. Analysis of Solar Active Regions and Activity from 22/2100Z to 23/2100Z: Solar activity was moderate. Region 9632 (S18E32) produced an M1/Sn flare at 1137 UTC, the day's only M-class event. That region is still large -- 780 millionths in white light area -- and magnetically complex. Other regions of note are 9622 (N13W45) and 9628 (S18E12). One new region was born on the disk, Region 9635 (N22E13), a simple bipole. IB. Solar Activity Forecast: Solar activity is expected to persist at the moderate level. IIA. Geophysical Activity Summary 22/2100Z to 23/2100Z: The geomagnetic field varied from quiet to minor storm levels in the past 24 hours. A shock passed the ACE spacecraft at about 0800 UTC, followed by an increase in solar wind radial speed to near 600 km/s. Periods of active to minor storm levels resulted from this fast solar wind. IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be unsettled to active throughout the forecast period. The current high speed solar wind stream may persist over the next few days, bringing occasional episodes of minor storm conditions to all latitudes. III. Event Probabilities 24 Sep-26 Sep Class M 70/70/70 Class X 10/10/10 Proton 05/05/05 PCAF green IV. Penticton 10.7 cm Flux Observed 23 Sep 259 Predicted 24 Sep-26 Sep 265/270/270 90 Day Mean 23 Sep 167 V. Geomagnetic A Indices Observed Afr/Ap 22 Sep 006/010 Estimated Afr/Ap 23 Sep 015/020 Predicted Afr/Ap 24 Sep-26 Sep 010/012-010/018-010/020 VI. Geomagnetic Activity Probabilities 24 Sep-26 Sep A. Middle Latitudes Active 30/30/30 Minor storm 10/10/10 Major-severe storm 01/01/01 B. High Latitudes Active 40/40/40 Minor storm 15/15/15 Major-severe storm 05/05/05
