Viewing archive of Thursday, 21 May 2009
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 2009 May 21 2201 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 2009IA. Analysis of Solar Active Regions and Activity from 20-2100Z to 21-2100Z Solar activity was very low. Region 1017 (N17W57) was
quiet. No flares were observed during the past 24 hours. The visible
disk remained spotless.
IB. Solar Activity Forecast
Solar activity is expected to be very
low.
IIA. Geophysical Activity Summary 20-2100Z to 21-2100Z
The geomagnetic field was quiet.
IIB. Geophysical Activity Forecast
The geomagnetic field is
expected to be predominantly quiet for the next three days (22-24
May).
III. Event Probabilities 22 May to 24 May
| Class M | 01% | 01% | 01% |
| Class X | 01% | 01% | 01% |
| Proton | 01% | 01% | 01% |
| PCAF | Green | ||
IV. Penticton 10.7 cm Flux
Observed 21 May 072 Predicted 22 May-24 May 071/070/070 90 Day Mean 21 May 070
V. Geomagnetic A Indices
Observed Afr/Ap 20 May 004/004 Estimated Afr/Ap 21 May 003/005 Predicted Afr/Ap 22 May-24 May 005/005-005/005-005/005
VI. Geomagnetic Activity Probabilities 22 May to 24 May
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 05% | 05% | 05% |
| Minor storm | 01% | 01% | 01% |
| Major-severe storm | 01% | 01% | 01% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 10% | 10% | 10% |
| Minor storm | 01% | 01% | 01% |
| Major-severe storm | 01% | 01% | 01% |
All times in UTC
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