Viewing archive of Thursday, 4 October 2001

Solar activity report

Any mentioned solar flare in this report has a scaling factor applied by the Space Weather Prediction Center (SWPC). Because of the SWPC scaling factor, solar flares are reported as 42% smaller than for the science quality data. The scaling factor has been removed from our archived solar flare data to reflect the true physical units.
Report of Solar-Geophysical Activity 2001 Oct 04 2200 UTC
Prepared by the NOAA © SWPC and processed by

Joint USAF/NOAA Report of Solar and Geophysical Activity

SDF Number 277 Issued at 2200Z on 04 Oct 2001

IA. Analysis of Solar Active Regions and Activity from 03-2100Z to 04-2100Z

Solar activity was low. Regions 9636 (N13W70) and 9645 (S17W41) produced C2/Sf events early in the period. Several Type III radio sweeps and discrete frequency radio bursts made up the rest of today's activity. The partial halo CME seen on EIT imagery yesterday appears to have been caused by a back-side source. Region 9636 and Region 9641 (S13W19) both showed an increase area coverage of their respective spot coverage today. Three new groups were numbered today, Region 9651 (S22W12), Region 9652 (N22E14), and Region 9653 (S23E76). Region 9653 has a penumbral spot that can be seen rotating onto the east limb and has a latitude of that in which old Region 9608 had as it departed the west limb.
IB. Solar Activity Forecast
Solar activity is expected to be moderate. Region 9636 and Region 9645 remain capable of producing M-class flares.
IIA. Geophysical Activity Summary 03-2100Z to 04-2100Z
The geomagnetic field was at quiet to minor storm levels. The greater than 10 MeV proton flux peaked at 02/0810 UTC, 2360 pfu. Flux levels remain above event level at time of bulletin issue.
IIB. Geophysical Activity Forecast
Geomagnetic activity is expected to be at quiet to unsettled levels with isolated active periods possible early on the first day of forecast period due to CME passage.
III. Event Probabilities 05 Oct to 07 Oct
Class M40%40%40%
Class X10%10%10%
IV. Penticton 10.7 cm Flux
  Observed       04 Oct 187
  Predicted   05 Oct-07 Oct  185/190/195
  90 Day Mean        04 Oct 180
V. Geomagnetic A Indices
  Observed Afr/Ap 03 Oct  026/053
  Estimated     Afr/Ap 04 Oct  015/020
  Predicted    Afr/Ap 05 Oct-07 Oct  010/010-008/010-008/010
VI. Geomagnetic Activity Probabilities 05 Oct to 07 Oct
A. Middle Latitudes
Minor storm05%05%05%
Major-severe storm01%01%01%
B. High Latitudes
Minor storm10%10%10%
Major-severe storm01%01%01%

All times in UTC

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