Viewing archive of Saturday, 17 September 2005
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 2005 Sep 17 2204 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 2005IA. Analysis of Solar Active Regions and Activity from 16-2100Z to 17-2100Z Solar activity was high. Region 808 (S11W50) produced
an M9/2n flare at 0605 UTC. The event included a radio burst of
1,000 sfu at 2695 MHz (tenflare) plus additional bursts across the
spectrum. The event apparently did not include a CME. The region,
though still potent, has declined in white light and simplified
slightly in its magnetic structure. Newly assigned Region 810
(N10E78) rotated into view.
IB. Solar Activity Forecast
Solar activity is expected to be
moderate to high. Region 808, though decaying, is still capable of
energetic activity.
IIA. Geophysical Activity Summary 16-2100Z to 17-2100Z
The geomagnetic field was quiet to unsettled. The greater than 2 MeV
geosynchronous electron flux was at very high levels.
IIB. Geophysical Activity Forecast
The geomagnetic field is
expected to be unsettled for the next three days.
III. Event Probabilities 18 Sep to 20 Sep
| Class M | 70% | 70% | 70% |
| Class X | 30% | 30% | 30% |
| Proton | 30% | 30% | 30% |
| PCAF | yellow | ||
IV. Penticton 10.7 cm Flux
Observed 17 Sep 104 Predicted 18 Sep-20 Sep 100/095/095 90 Day Mean 17 Sep 093
V. Geomagnetic A Indices
Observed Afr/Ap 16 Sep 011/018 Estimated Afr/Ap 17 Sep 010/012 Predicted Afr/Ap 18 Sep-20 Sep 010/010-010/010-010/015
VI. Geomagnetic Activity Probabilities 18 Sep to 20 Sep
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 20% | 20% | 20% |
| Minor storm | 10% | 10% | 10% |
| Major-severe storm | 05% | 05% | 05% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 30% | 30% | 30% |
| Minor storm | 15% | 15% | 15% |
| Major-severe storm | 05% | 05% | 05% |
All times in UTC
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