Viewing archive of Saturday, 20 August 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 Aug 20 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 232 Issued at 2200Z on 20 Aug 2011IA. Analysis of Solar Active Regions and Activity from 19-2100Z to 20-2100Z Solar activity was very low. There were occasional
B-class flares from Regions 1272 (S22E15) and 1271 (N16E10). Region
1271 decayed slightly to become a Dso type spot group with Beta
magnetic configuration. Region 1274 (N19E70) was numbered today; it
is currently small and magnetically simple.
IB. Solar Activity Forecast
Solar activity is expected to be very
low to low on Day 1 (21 Aug), becoming low with a slight chance for
moderate activity on Days 2 and 3 (22-23 Aug) with four active
regions expected to be on the disk at that time.
IIA. Geophysical Activity Summary 19-2100Z to 20-2100Z
The geomagnetic field was quiet and the solar wind at the ACE
spacecraft was unremarkable.
IIB. Geophysical Activity Forecast
The geomagnetic field is
expected to be quiet to unsettled on Day 1 (21 Aug) rising to
unsettled with a chance for active conditions on Day 2 (22 Aug).
The increase in activity is expected due to a co-rotating
interaction region followed by two negative polarity coronal hole
high speed streams. Day 3 (23 Aug) is expected to return to quiet
to unsettled conditions as effects from the first coronal hole begin
to wane.
III. Event Probabilities 21 Aug to 23 Aug
| Class M | 05% | 20% | 20% |
| Class X | 01% | 01% | 01% |
| Proton | 01% | 01% | 01% |
| PCAF | Green | ||
IV. Penticton 10.7 cm Flux
Observed 20 Aug 101 Predicted 21 Aug-23 Aug 102/104/105 90 Day Mean 20 Aug 096
V. Geomagnetic A Indices
Observed Afr/Ap 19 Aug 001/002 Estimated Afr/Ap 20 Aug 003/003 Predicted Afr/Ap 21 Aug-23 Aug 007/008-010/012-007/008
VI. Geomagnetic Activity Probabilities 21 Aug to 23 Aug
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 15% | 25% | 15% |
| Minor storm | 05% | 10% | 05% |
| Major-severe storm | 01% | 05% | 01% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 30% | 40% | 30% |
| Minor storm | 15% | 20% | 15% |
| Major-severe storm | 05% | 10% | 05% |
All times in UTC
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