Viewing archive of Thursday, 22 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 22 2225 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
:::::::::: CORRECTED COPY :::::::::: SDF Number 265 Issued at 2200Z on 22 Sep 2011IA. Analysis of Solar Active Regions and Activity from 21-2100Z to 22-2100Z
Activity was high. New Region 1302 (N11E74) produced a
long-duration X1/2n flare at 22/1101Z. The X1 flare was associated
with Types II and IV radio sweeps, a 970 sfu Tenflare, and a full
halo CME. The CME, already in progress in SOHO LASCO images at
22/1330Z, had an estimated speed of around 1392 km/s. This CME is
not expected to be geoeffective.
IB. Solar Activity Forecast
Solar activity is expected to be high,
with a slight chance for another X-class flare from Region 1302.
IIA. Geophysical Activity Summary 21-2100Z to 22-2100Z
The geomagnetic field was quiet.
IIB. Geophysical Activity Forecast
The geomagnetic field is
expected to be quiet on days one and two (23-24 September). Quiet to
unsettled levels, with isolated active levels at high latitudes, are
expected on day three (25 September), due to a weak coronal hole
high-speed stream.
III. Event Probabilities 23 Sep to 25 Sep
| Class M | 70% | 70% | 70% |
| Class X | 20% | 20% | 20% |
| Proton | 10% | 10% | 10% |
| PCAF | green | ||
IV. Penticton 10.7 cm Flux
Observed 22 Sep 151 Predicted 23 Sep-25 Sep 155/160/165 90 Day Mean 22 Sep 105
V. Geomagnetic A Indices
Observed Afr/Ap 21 Sep 002/005 Estimated Afr/Ap 22 Sep 003/004 Predicted Afr/Ap 23 Sep-25 Sep 005/005-005/005-007/008
VI. Geomagnetic Activity Probabilities 23 Sep to 25 Sep
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 05% | 05% | 10% |
| Minor storm | 01% | 01% | 01% |
| Major-severe storm | 01% | 01% | 01% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 10% | 10% | 15% |
| Minor storm | 01% | 01% | 01% |
| Major-severe storm | 01% | 01% | 01% |
All times in UTC
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