Viewing archive of Thursday, 17 September 2009
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 2009 Sep 17 2201 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 260 Issued at 2200Z on 17 Sep 2009IA. Analysis of Solar Active Regions and Activity from 16-2100Z to 17-2100Z Solar activity was very low. No flares were observed.
The visible disk remains spotless.
IB. Solar Activity Forecast
Solar activity is expected to remain
very low.
IIA. Geophysical Activity Summary 16-2100Z to 17-2100Z
The geomagnetic field was predominantly quiet with two periods of
unsettled conditions from 0000Z-0600Z.
IIB. Geophysical Activity Forecast
The geomagnetic field is
expected to remain quiet with isolated periods of unsettled
conditions for day one (18 September). This activity is due to a
recurrent coronal hole high speed stream. On days two and three
(19-20 September), the geomagnetic field is expected to return to
quiet levels.
III. Event Probabilities 18 Sep to 20 Sep
| Class M | 01% | 01% | 01% |
| Class X | 01% | 01% | 01% |
| Proton | 01% | 01% | 01% |
| PCAF | Green | ||
IV. Penticton 10.7 cm Flux
Observed 17 Sep 069 Predicted 18 Sep-20 Sep 069/070/070 90 Day Mean 17 Sep 068
V. Geomagnetic A Indices
Observed Afr/Ap 16 Sep 005/006 Estimated Afr/Ap 17 Sep 007/010 Predicted Afr/Ap 18 Sep-20 Sep 005/008-005/005-005/005
VI. Geomagnetic Activity Probabilities 18 Sep to 20 Sep
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 05% | 05% | 05% |
| Minor storm | 01% | 01% | 01% |
| Major-severe storm | 01% | 01% | 01% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 05% | 05% | 05% |
| Minor storm | 01% | 01% | 01% |
| Major-severe storm | 01% | 01% | 01% |
All times in UTC
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