Viewing archive of Friday, 11 May 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 May 11 2200 UTC
Prepared by the NOAA © SWPC and processed by

Joint USAF/NOAA Report of Solar and Geophysical Activity

SDF Number 131 Issued at 2200Z on 11 May 2001

IA. Analysis of Solar Active Regions and Activity from 10-2100Z to 11-2100Z

Solar activity was low during the last 24 hours. Three C-class flares occurred including a C1 at 0717 UTC, a C1/Sf from newly assigned 9455 (S18E17) at 1006 UTC, and a C3 apparently from 9455 at 2022 UTC. New Region 9455 grew quickly on the disk to a D-type sunspot group and appears to have a weak delta configuration. Region 9454 (S18E17) continues to be the largest group on the disk at 430 millionths. The group was not observed to produce any flares, but did exhibit frequent plage fluctuations throughout the day. It appears to have a simple beta magnetic configuration. An 18 degree filament near S11E14 disappeared sometime between 0507 UTC and 1314 UTC.
IB. Solar Activity Forecast
Solar activity is expected to be mostly low, but there is a fair chance for an isolated M-class event from either of Region 9454 or Region 9455.
IIA. Geophysical Activity Summary 10-2100Z to 11-2100Z
The geomagnetic field has been quiet to unsettled during the past 24 hours. The greater than 2 MeV electron fluxes attained high levels today.
IIB. Geophysical Activity Forecast
The geomagnetic field is expected to be quiet to unsettled for the next three days.
III. Event Probabilities 12 May to 14 May
Class M25%25%25%
Class X05%05%05%
IV. Penticton 10.7 cm Flux
  Observed       11 May 137
  Predicted   12 May-14 May  140/145/150
  90 Day Mean        11 May 167
V. Geomagnetic A Indices
  Observed Afr/Ap 10 May  023/028
  Estimated     Afr/Ap 11 May  008/008
  Predicted    Afr/Ap 12 May-14 May  007/008-007/009-007/009
VI. Geomagnetic Activity Probabilities 12 May to 14 May
A. Middle Latitudes
Minor storm05%05%05%
Major-severe storm05%05%05%
B. High Latitudes
Minor storm10%10%10%
Major-severe storm05%05%05%

All times in UTC

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