Viewing archive of Monday, 16 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 16 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 106 Issued at 2200Z on 16 Apr 2001IA. Analysis of Solar Active Regions and Activity from 15-2100Z to 16-2100Z Solar activity was moderate. An optically uncorrelated
M1 event occurred at 16/0622 UTC. New Region 9430 (S16W33) was
numbered today.
IB. Solar Activity Forecast
Solar activity is expected to be low
to moderate.
IIA. Geophysical Activity Summary 15-2100Z to 16-2100Z
The geomagnetic field was quiet to unsettled. The greater than 10
MeV and greater than 100 MeV proton events that started yesterday
are still in progress. Peak flux for the greater than 10 MeV
protons was 951 pfu at 15/1920 UTC and the peak flux for the greater
than 100 MeV was 146 pfu at 15/1525 UTC. The greater than 2 MeV
electrons at geosynchronous orbit were at high levels and remained
above threshold through the period. The polar cap absorption (PCA)
event that started yesterday is still in progress.
IIB. Geophysical Activity Forecast
The geomagnetic field is
expected to be unsettled to active for April 17. Active to minor
storm conditions are expected for April 18 as a result of the X14/2b
flare on April 15, and possible effects from a well positioned
coronal hole. Unsettled to active conditions are expected to return
on April 19. The greater than 10 MeV proton event is expected to
continue for most of the period, and the greater than 100 MeV proton
event is expected to go below threshold sometime on April 17.
III. Event Probabilities 17 Apr to 19 Apr
| Class M | 70% | 60% | 50% |
| Class X | 25% | 10% | 10% |
| Proton | 99% | 50% | 10% |
| PCAF | in progress | ||
IV. Penticton 10.7 cm Flux
Observed 16 Apr 123 Predicted 17 Apr-19 Apr 130/140/150 90 Day Mean 16 Apr 165
V. Geomagnetic A Indices
Observed Afr/Ap 15 Apr 009/013 Estimated Afr/Ap 16 Apr 010/012 Predicted Afr/Ap 17 Apr-19 Apr 015/020-020/035-015/030
VI. Geomagnetic Activity Probabilities 17 Apr to 19 Apr
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 25% | 50% | 25% |
| Minor storm | 05% | 10% | 05% |
| Major-severe storm | 01% | 05% | 01% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 35% | 60% | 50% |
| Minor storm | 10% | 15% | 15% |
| Major-severe storm | 05% | 10% | 10% |
All times in UTC
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