Viewing archive of Wednesday, 21 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 21 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 264 Issued at 2200Z on 21 Sep 2011IA. Analysis of Solar Active Regions and Activity from 20-2100Z to 21-2100Z
Solar activity was moderate. An M1 flare was observed
at 21/1223Z from Region 1301 (N20E41). Regions 1295 (N22W47) and
1301 showed increases in area and produced occasional C-class flares
during the period. Three CMEs were observed towards the NE quadrant,
none of which are expected to be geoeffective.
IB. Solar Activity Forecast
Solar activity is expected to be low
with a chance for isolated M-class flares from Regions 1295 and 1301
during the period (22-24 September).
IIA. Geophysical Activity Summary 20-2100Z to 21-2100Z
The geomagnetic field was at quiet levels at mid-latitudes, with
isolated unsettled to active levels at high-latitudes.
IIB. Geophysical Activity Forecast
The geomagnetic field is
expected to be at predominantly quiet levels during the period
(22-24 September).
III. Event Probabilities 22 Sep to 24 Sep
| Class M | 45% | 45% | 45% |
| Class X | 10% | 10% | 10% |
| Proton | 01% | 01% | 01% |
| PCAF | green | ||
IV. Penticton 10.7 cm Flux
Observed 21 Sep 144 Predicted 22 Sep-24 Sep 144/144/140 90 Day Mean 21 Sep 104
V. Geomagnetic A Indices
Observed Afr/Ap 20 Sep 006/006 Estimated Afr/Ap 21 Sep 004/005 Predicted Afr/Ap 22 Sep-24 Sep 005/005-005/005-005/005
VI. Geomagnetic Activity Probabilities 22 Sep to 24 Sep
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 05% | 05% | 05% |
| Minor storm | 01% | 01% | 01% |
| Major-severe storm | 01% | 01% | 01% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 10% | 10% | 10% |
| Minor storm | 01% | 01% | 01% |
| Major-severe storm | 01% | 01% | 01% |
All times in UTC
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