Viewing archive of Friday, 20 May 2011
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 2011 May 20 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 140 Issued at 2200Z on 20 May 2011IA. Analysis of Solar Active Regions and Activity from 19-2100Z to 20-2100Z Solar activity was very low. The three spotted regions
on the disk, 1214 (S24W70), 1216 (S16E19) and 1218 (S16E40) were all
unipolar and magnetically simple.
IB. Solar Activity Forecast
Solar activity is expected to remain
very low to low. A slight chance for a C-class x-ray flare remains
for the next three days (21 May - 23 May).
IIA. Geophysical Activity Summary 19-2100Z to 20-2100Z
The geomagnetic field was quiet. A weak sudden impulse (3nT) at the
Boulder magnetometer was observed at 20/0415Z.
IIB. Geophysical Activity Forecast
The geomagnetic field is
expected to remain predominantly quiet for the next three days (21
May - 23 May).
III. Event Probabilities 21 May to 23 May
| Class M | 01% | 01% | 01% |
| Class X | 01% | 01% | 01% |
| Proton | 01% | 01% | 01% |
| PCAF | green | ||
IV. Penticton 10.7 cm Flux
Observed 20 May 084 Predicted 21 May-23 May 083/080/080 90 Day Mean 20 May 108
V. Geomagnetic A Indices
Observed Afr/Ap 19 May 002/004 Estimated Afr/Ap 20 May 005/005 Predicted Afr/Ap 21 May-23 May 005/005-005/005-005/005
VI. Geomagnetic Activity Probabilities 21 May to 23 May
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 10% | 10% | 05% |
| Minor storm | 01% | 01% | 01% |
| Major-severe storm | 01% | 01% | 01% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 15% | 15% | 10% |
| Minor storm | 05% | 05% | 05% |
| Major-severe storm | 01% | 01% | 01% |
All times in UTC
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