Viewing archive of Friday, 19 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 19 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 231 Issued at 2200Z on 19 Aug 2011IA. Analysis of Solar Active Regions and Activity from 18-2100Z to 19-2100Z Solar activity was very low. Region 1271 (N16E25) did
not produce any significant activity during the past 24 hours,
although it did retain a large Esi type spot group with beta-gamma
magnetic characteristics. The other two regions were small and
simple.
IB. Solar Activity Forecast
Solar activity is expected to be low
on Day 1 (20 Aug), becoming low with a chance for moderate activity
on Days 2 and 3 (21-22 Aug) when old Region 1261 (N15, L=347)
returns.
IIA. Geophysical Activity Summary 18-2100Z to 19-2100Z
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 at quiet levels on Day 1 (20 Aug) and rise to
unsettled levels with a chance for active conditions on Day 2 (21
Aug). The rise in activity is expected with the arrival of a
coronal hole high speed stream. By Day 3 (22 Aug), a return to
mostly quiet conditions is expected as weak coronal hole effects
wane.
III. Event Probabilities 20 Aug to 22 Aug
| Class M | 05% | 45% | 45% |
| Class X | 01% | 05% | 10% |
| Proton | 01% | 01% | 01% |
| PCAF | Green | ||
IV. Penticton 10.7 cm Flux
Observed 19 Aug 098 Predicted 20 Aug-22 Aug 100/100/100 90 Day Mean 19 Aug 096
V. Geomagnetic A Indices
Observed Afr/Ap 18 Aug 001/003 Estimated Afr/Ap 19 Aug 003/003 Predicted Afr/Ap 20 Aug-22 Aug 005/005-010/012-005/005
VI. Geomagnetic Activity Probabilities 20 Aug to 22 Aug
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 15% | 25% | 10% |
| Minor storm | 05% | 10% | 05% |
| Major-severe storm | 01% | 05% | 05% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 10% | 50% | 20% |
| Minor storm | 05% | 15% | 05% |
| Major-severe storm | 01% | 10% | 05% |
All times in UTC
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