Viewing archive of Sunday, 18 September 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 Sep 18 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 261 Issued at 2200Z on 18 Sep 2011IA. Analysis of Solar Active Regions and Activity from 17-2100Z to 18-2100Z Solar activity was low. Region 1295 (N22W12) produced a
long duration C3 flare at 18/1057Z. A back-sided CME was observed on
LASCO C3 imagery at 18/1242Z. Region 1295 was classified as a beta
gamma magnetic configuration again today. Regions 1300 (N24W45) and
1301 (N21E77) were numbered during the past 24 hours.
IB. Solar Activity Forecast
Solar activity is expected to be low
with a chance for isolated M-class flares from Region 1295 for the
next three days (19-21 September).
IIA. Geophysical Activity Summary 17-2100Z to 18-2100Z
The geomagnetic field was mostly quiet.
IIB. Geophysical Activity Forecast
The geomagnetic field is
expected to be quiet for the next three days (19-21 September).
III. Event Probabilities 19 Sep to 21 Sep
| Class M | 35% | 35% | 35% |
| Class X | 01% | 01% | 01% |
| Proton | 01% | 01% | 01% |
| PCAF | green | ||
IV. Penticton 10.7 cm Flux
Observed 18 Sep 150 Predicted 19 Sep-21 Sep 150/150/150 90 Day Mean 18 Sep 103
V. Geomagnetic A Indices
Observed Afr/Ap 17 Sep 014/032 Estimated Afr/Ap 18 Sep 005/008 Predicted Afr/Ap 19 Sep-21 Sep 005/005-005/005-005/005
VI. Geomagnetic Activity Probabilities 19 Sep to 21 Sep
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 10% | 05% | 05% |
| Minor storm | 01% | 01% | 01% |
| Major-severe storm | 01% | 01% | 01% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 10% | 05% | 05% |
| Minor storm | 01% | 01% | 01% |
| Major-severe storm | 01% | 01% | 01% |
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