Viewing archive of Monday, 20 September 2010
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 2010 Sep 20 2201 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 263 Issued at 2200Z on 20 Sep 2010IA. Analysis of Solar Active Regions and Activity from 19-2100Z to 20-2100Z
Solar activity was low. A C2 X-ray event was observed
at 20/1945Z. The event appeared to originate from an emerging flux
region on the east limb near N20. Region 1106 (S21W53) decayed in
the trailer portion of the spot group, but maintained a bi-polar
magnetic configuration. Region 1108 (S30E24) exhibited little change
during the period.
IB. Solar Activity Forecast
Solar activity is expected to be very
low to low with a slight chance of M-class activity for the next
three days (21 - 23 September).
IIA. Geophysical Activity Summary 19-2100Z to 20-2100Z
The geomagnetic field was quiet.
IIB. Geophysical Activity Forecast
The geomagnetic field is
expected to be at quiet to unsettled levels, with isolated active
periods, for day one (21 September). Mostly unsettled, with
isolated active to minor storm levels, are expected on days two and
three (22 - 23 September). The increase in activity is due to a
large, recurrent coronal hole high speed stream.
III. Event Probabilities 21 Sep to 23 Sep
| Class M | 10% | 10% | 10% |
| Class X | 01% | 01% | 01% |
| Proton | 01% | 01% | 01% |
| PCAF | Green | ||
IV. Penticton 10.7 cm Flux
Observed 20 Sep 083 Predicted 21 Sep-23 Sep 083/083/084 90 Day Mean 20 Sep 078
V. Geomagnetic A Indices
Observed Afr/Ap 19 Sep 002/004 Estimated Afr/Ap 20 Sep 003/005 Predicted Afr/Ap 21 Sep-23 Sep 008/012-015/018-015/018
VI. Geomagnetic Activity Probabilities 21 Sep to 23 Sep
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 20% | 30% | 30% |
| Minor storm | 01% | 05% | 05% |
| Major-severe storm | 01% | 01% | 01% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 25% | 35% | 35% |
| Minor storm | 05% | 10% | 10% |
| Major-severe storm | 01% | 01% | 01% |
All times in UTC
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