Viewing archive of Thursday, 27 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 27 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 271 Issued at 2200Z on 27 Sep 2012IA. Analysis of Solar Active Regions and Activity from 26-2100Z to 27-2100Z
Solar activity has been at low levels for the past 24
hours. The largest solar flare of the period was an C4/Sf at 1720Z
from an unnumbered region around S18E39. There are currently 9
numbered sunspot regions on the visible disk, however most have
remained rather stable and quiet. A non-Earth directed full halo CME
was observed in both STEREO A-B and LASCO imagery early in the
period.
IB. Solar Activity Forecast
Solar activity is expected to be at
low levels with a slight chance for M-class activity for the next
three days (28 - 30 September).
IIA. Geophysical Activity Summary 26-2100Z to 27-2100Z
The geomagnetic field has been at quiet levels for the past 24 hours.
IIB. Geophysical Activity Forecast
The geomagnetic field is
expected to be at predominantly quiet levels for the next three days
(28 - 30 September).
III. Event Probabilities 28 Sep to 30 Sep
| Class M | 10% | 10% | 10% |
| Class X | 01% | 01% | 01% |
| Proton | 01% | 01% | 01% |
| PCAF | green | ||
IV. Penticton 10.7 cm Flux
Observed 27 Sep 133 Predicted 28 Sep-30 Sep 130/130/125 90 Day Mean 27 Sep 124
V. Geomagnetic A Indices
Observed Afr/Ap 26 Sep 006/007 Estimated Afr/Ap 27 Sep 005/005 Predicted Afr/Ap 28 Sep-30 Sep 005/005-006/005-006/005
VI. Geomagnetic Activity Probabilities 28 Sep to 30 Sep
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 05% | 05% | 05% |
| Minor storm | 01% | 01% | 01% |
| Major-severe storm | 01% | 01% | 01% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 15% | 15% | 15% |
| Minor storm | 15% | 15% | 15% |
| Major-severe storm | 05% | 05% | 05% |
All times in UTC
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