Viewing archive of Friday, 21 September 2012
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 2012 Sep 21 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 265 Issued at 2200Z on 21 Sep 2012IA. Analysis of Solar Active Regions and Activity from 20-2100Z to 21-2100Z
Solar activity was very low. The largest x-ray event
was a B8/Sf at 21/1221Z produced by Region 1573 (N18W04). The
largest spot group on the solar disk, Region 1575 (N08E37), remains
near 250 millionths in area with a Beta magnetic configuration. Two
asymmetrical partial halo CMEs were observed in SOHO LASCO during
the period. Both events were determined to be backside sourced, and
are not expected to impact Earth.
IB. Solar Activity Forecast
Solar activity is expected to be very
low to low for the next 3 days (22-24 September).
IIA. Geophysical Activity Summary 20-2100Z to 21-2100Z
The geomagnetic field was quiet during the period, despite the
influence of a weak coronal hole (CH) high speed stream.
IIB. Geophysical Activity Forecast
The geomagnetic field is
expected to be quiet to unsettled for day 1 (22 September) as CH
effects wane. Conditions are expected to be mostly quiet for days
2-3 (23-24 September).
III. Event Probabilities 22 Sep to 24 Sep
| Class M | 05% | 05% | 05% |
| Class X | 01% | 01% | 01% |
| Proton | 01% | 01% | 01% |
| PCAF | green | ||
IV. Penticton 10.7 cm Flux
Observed 21 Sep 117 Predicted 22 Sep-24 Sep 118/120/120 90 Day Mean 21 Sep 122
V. Geomagnetic A Indices
Observed Afr/Ap 20 Sep 010/010 Estimated Afr/Ap 21 Sep 005/006 Predicted Afr/Ap 22 Sep-24 Sep 008/008-006/005-006/005
VI. Geomagnetic Activity Probabilities 22 Sep to 24 Sep
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 10% | 01% | 01% |
| Minor storm | 01% | 01% | 01% |
| Major-severe storm | 01% | 01% | 01% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 15% | 15% | 15% |
| Minor storm | 20% | 10% | 10% |
| Major-severe storm | 15% | 05% | 05% |
All times in UTC
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