Viewing archive of Monday, 17 September 2001

Solar activity report

Report of Solar-Geophysical Activity 2001 Sep 17 2200 UTC
Prepared by the NOAA © SWPC and processed by

Joint USAF/NOAA Report of Solar and Geophysical Activity

SDF Number 260 Issued at 2200Z on 17 Sep 2001

IA. Analysis of Solar Active Regions and Activity from 16-2100Z to 17-2100Z

Solar activity was high. Region 9616 (S12E03) produced an M1/2n impulsive flare at 17/0825 UTC accompanied by a Type II radio sweep (764 km/s) and a 460 sfu Tenflare. LASCO/EIT observed a partial halo CME associated with this event. Region 9608 (S30W75) produced an M8/1n at 17/1550 UTC with an associated 380 sfu Tenflare. New Region's 9622 (N12E34), 9623 (N21E46), and 9624 (N03E70) were numbered today.
IB. Solar Activity Forecast
Solar activity is expected to be moderate to high with Region's 9608 and 9616 still proving to have potential to produce a major flare.
IIA. Geophysical Activity Summary 16-2100Z to 17-2100Z
The geomagnetic field has been quiet to unsettled.
IIB. Geophysical Activity Forecast
The geomagnetic field is expected to be quiet to unsettled. Active conditions are possible for the next three days as a result of the CME activity over the past few days and a recurrent high speed stream in the solar wind.
III. Event Probabilities 18 Sep to 20 Sep
Class M80%80%80%
Class X15%15%15%
IV. Penticton 10.7 cm Flux
  Observed       17 Sep 199
  Predicted   18 Sep-20 Sep  195/195/200
  90 Day Mean        17 Sep 165
V. Geomagnetic A Indices
  Observed Afr/Ap 16 Sep  007/008
  Estimated     Afr/Ap 17 Sep  010/010
  Predicted    Afr/Ap 18 Sep-20 Sep  015/018-015/015-015/015
VI. Geomagnetic Activity Probabilities 18 Sep to 20 Sep
A. Middle Latitudes
Minor storm10%10%10%
Major-severe storm05%05%05%
B. High Latitudes
Minor storm15%15%15%
Major-severe storm05%05%05%

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