Viewing archive of Friday, 21 September 2001

Solar activity report

Report of Solar-Geophysical Activity 2001 Sep 21 2200 UTC
Prepared by the NOAA © SWPC and processed by SpaceWeatherLive.com

Joint USAF/NOAA Report of Solar and Geophysical Activity

SDF Number 264 Issued at 2200Z on 21 Sep 2001

IA. Analysis of Solar Active Regions and Activity from 20-2100Z to 21-2100Z

Solar activity was low. The largest flare of the past day was a C7/Sf at 21/0702 UTC in Region 9631 (N09W24). Regions 9620 (N11E04), 9628 (S18E38), and 9632 (S17E56) also produced C-class subflares. The largest, most magnetically complex sunspot groups appear to be 9628 and 9632.
IB. Solar Activity Forecast
Solar activity is expected to be low to moderate. M-class activity is possible from a number of areas, including Regions 9620, 9628, and 9632.
IIA. Geophysical Activity Summary 20-2100Z to 21-2100Z
The geomagnetic field was quiet to unsettled.
IIB. Geophysical Activity Forecast
The geomagnetic field is expected to be quiet to unsettled.
III. Event Probabilities 22 Sep to 24 Sep
Class M80%80%80%
Class X10%10%10%
Proton05%05%05%
PCAFgreen
IV. Penticton 10.7 cm Flux
  Observed       21 Sep 239
  Predicted   22 Sep-24 Sep  245/250/250
  90 Day Mean        21 Sep 165
V. Geomagnetic A Indices
  Observed Afr/Ap 20 Sep  007/005
  Estimated     Afr/Ap 21 Sep  006/009
  Predicted    Afr/Ap 22 Sep-24 Sep  010/015-010/012-010/010
VI. Geomagnetic Activity Probabilities 22 Sep to 24 Sep
A. Middle Latitudes
Active20%20%20%
Minor storm05%05%05%
Major-severe storm01%01%01%
B. High Latitudes
Active30%30%30%
Minor storm10%10%10%
Major-severe storm01%01%01%

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