Viewing archive of Saturday, 21 May 2005
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 2005 May 21 2210 UTC# Prepared jointly by the U.S. Dept. of Commerce, NOAA, #Space Environment Center and the U.S. Air Force. #
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 141 Issued at 2200Z on 21 May 2005IA. Analysis of Solar Active Regions and Activity from 20-2100Z to 21-2100Z Solar activity was very low.
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 to active. Active periods were the
result of a prolonged southward Bz.
IIB. Geophysical Activity Forecast
The geomagnetic field is
expected to be quiet to unsettled with the possibility of an
isolated active period on 22 May. On 23 and 24 May, quiet to
unsettled conditions are expected.
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 082 Predicted 22 May-24 May 085/090/090 90 Day Mean 21 May 091
V. Geomagnetic A Indices
Observed Afr/Ap 20 May 017/030 Estimated Afr/Ap 21 May 008/020 Predicted Afr/Ap 22 May-24 May 006/015-004/010-004/008
VI. Geomagnetic Activity Probabilities 22 May to 24 May
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 15% | 10% | 10% |
| Minor storm | 05% | 05% | 05% |
| Major-severe storm | 01% | 01% | 01% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 25% | 20% | 20% |
| Minor storm | 15% | 10% | 10% |
| Major-severe storm | 05% | 01% | 01% |
All times in UTC
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