Viewing archive of Monday, 21 May 2007
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 2007 May 21 2203 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 141 Issued at 2200Z on 21 May 2007IA. Analysis of Solar Active Regions and Activity from 20-2100Z to 21-2100Z Solar activity was very low. Region 956 (N03W32) is
decaying but continues to produce occasional B-class flares.
IB. Solar Activity Forecast
Solar activity is expected to continue
at very low levels. There is slight chance for a C-class flare from
Region 956.
IIA. Geophysical Activity Summary 20-2100Z to 21-2100Z
The geomagnetic field was quiet with isolated unsettled periods. The
greater than 2 MeV electron flux at geosynchronous orbit reached
high levels today.
IIB. Geophysical Activity Forecast
The geomagnetic field is
expected to range from quiet to minor storm levels. A weak CME
observed on 19 May may produce isolated unsettled to active periods
on 22 May. A high speed coronal hole stream will rotate into a
geoeffective position on 24 May and produce occasional active to
minor storm periods.
III. Event Probabilities 22 May to 24 May
| Class M | 05% | 05% | 05% |
| Class X | 01% | 01% | 01% |
| Proton | 01% | 01% | 01% |
| PCAF | green | ||
IV. Penticton 10.7 cm Flux
Observed 21 May 073 Predicted 22 May-24 May 075/075/075 90 Day Mean 21 May 074
V. Geomagnetic A Indices
Observed Afr/Ap 20 May 006/006 Estimated Afr/Ap 21 May 005/012 Predicted Afr/Ap 22 May-24 May 005/008-005/005-010/015
VI. Geomagnetic Activity Probabilities 22 May to 24 May
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 15% | 15% | 30% |
| Minor storm | 01% | 01% | 10% |
| Major-severe storm | 01% | 01% | 05% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 20% | 20% | 40% |
| Minor storm | 05% | 05% | 20% |
| Major-severe storm | 01% | 01% | 10% |
All times in UTC
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