Viewing archive of Saturday, 21 April 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 Apr 21 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 111 Issued at 2200Z on 21 Apr 2001IA. Analysis of Solar Active Regions and Activity from 20-2100Z to 21-2100Z Solar activity has been low. The largest flare was a
C8 x-ray burst that occurred at 20/2134 UTC. No optical flare
reports were received but space-based images identify Region 9433
(N16E40) as the source. Regions 9436 (S11E72) and 9437 (N08E76)
were numbered.
IB. Solar Activity Forecast
Solar activity is expected to be
moderate. Region 9433 is expected to be the source of most activity.
IIA. Geophysical Activity Summary 20-2100Z to 21-2100Z
The geomagnetic field was quiet to active.
IIB. Geophysical Activity Forecast
The geomagnetic field is
expected to be quiet to unsettled.
III. Event Probabilities 22 Apr to 24 Apr
| Class M | 75% | 75% | 75% |
| Class X | 10% | 10% | 10% |
| Proton | 05% | 05% | 05% |
| PCAF | green | ||
IV. Penticton 10.7 cm Flux
Observed 21 Apr 191 Predicted 22 Apr-24 Apr 200/210/220 90 Day Mean 21 Apr 165
V. Geomagnetic A Indices
Observed Afr/Ap 20 Apr 005/008 Estimated Afr/Ap 21 Apr 010/008 Predicted Afr/Ap 22 Apr-24 Apr 005/010-010/010-010/010
VI. Geomagnetic Activity Probabilities 22 Apr to 24 Apr
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 20% | 20% | 20% |
| Minor storm | 10% | 10% | 10% |
| Major-severe storm | 01% | 01% | 01% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 20% | 20% | 20% |
| Minor storm | 10% | 10% | 10% |
| Major-severe storm | 01% | 01% | 01% |
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