Viewing archive of Thursday, 10 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 10 2200 UTC
Prepared by the NOAA © SWPC and processed by

Joint USAF/NOAA Report of Solar and Geophysical Activity

SDF Number 130 Issued at 2200Z on 10 May 2001

IA. Analysis of Solar Active Regions and Activity from 09-2100Z to 10-2100Z

Solar activity has been low during the past 24 hours. Two noteworthy C-class events occurred during the day. The first was a C5 which started at 0105 UTC, reached maximum at 0203 UTC, and ended at 0443 UTC. There were no observations of corresponding disk activity, but there was a CME just behind the Northwest limb of the Sun that could be reasonably associated with the event. The other was a C6 with start-max-end times of 1448-1519-1547 UTC: newly assigned Region 9454 (N15E74) was seen to brighten in H-alpha during the event, and a CME became visible on the East limb in C2 observations at 1530 UTC. A type II sweep was also associated with this event. New Region 9454 is now the largest sunspot group on the disk with an area of 300 millionths in an Eao-Beta configuration.
IB. Solar Activity Forecast
Solar activity is expected to be mostly low, but there is a chance for an isolated M-class event from Region 9454.
IIA. Geophysical Activity Summary 09-2100Z to 10-2100Z
The geomagnetic field ranged from quiet to minor storm levels. An initially active geomagnetic field reached minor storm levels between 0000-0900 UTC. Conditions declined thereafter and were quiet to unsettled during the last nine hours of the day.
IIB. Geophysical Activity Forecast
The geomagnetic field is expected to be mostly unsettled during the next three days.
III. Event Probabilities 11 May to 13 May
Class M20%20%20%
Class X01%01%01%
IV. Penticton 10.7 cm Flux
  Observed       10 May 130
  Predicted   11 May-13 May  135/135/135
  90 Day Mean        10 May 168
V. Geomagnetic A Indices
  Observed Afr/Ap 09 May  019/032
  Estimated     Afr/Ap 10 May  028/035
  Predicted    Afr/Ap 11 May-13 May  015/015-010/010-010/010
VI. Geomagnetic Activity Probabilities 11 May to 13 May
A. Middle Latitudes
Minor storm25%20%20%
Major-severe storm10%05%05%
B. High Latitudes
Minor storm30%25%25%
Major-severe storm15%10%10%

All times in UTC

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