Viewing archive of Friday, 16 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 16 2204 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 259 Issued at 2200Z on 16 Sep 2005IA. Analysis of Solar Active Regions and Activity from 15-2100Z to 16-2100Z
Solar activity was at moderate levels. Region 808
(S11W37) produced three M-class flares. The largest of these was an
M4.4/1b flare at 16/0149 UTC. The area of Region 808 has decayed to
approximately 620 millionths; however, the region still exhibits a
beta-gamma-delta magnetic configuration.
IB. Solar Activity Forecast
Solar activity is expected to be
moderate to high.
IIA. Geophysical Activity Summary 15-2100Z to 16-2100Z
The geomagnetic field was at quiet to active levels. Active levels
were the result of the high solar wind speeds early in the UTC day.
The solar wind speed declined over the past 24 hours from about 750
km/s to about 625 km/s. The greater than 10 MeV proton event that
began at 08/0215 UTC and reached a maximum of 1880 pfu at 11/0425
UTC ended at 16/0025 UTC. The greater than 2 MeV electron flux at
geosynchronous orbit was at high levels again today.
IIB. Geophysical Activity Forecast
The geomagnetic field is
expected to be at mostly unsettled levels for the next three days.
III. Event Probabilities 17 Sep to 19 Sep
| Class M | 70% | 60% | 60% |
| Class X | 40% | 30% | 30% |
| Proton | 30% | 30% | 30% |
| PCAF | yellow | ||
IV. Penticton 10.7 cm Flux
Observed 16 Sep 112 Predicted 17 Sep-19 Sep 110/110/105 90 Day Mean 16 Sep 093
V. Geomagnetic A Indices
Observed Afr/Ap 15 Sep 022/043 Estimated Afr/Ap 16 Sep 015/020 Predicted Afr/Ap 17 Sep-19 Sep 008/015-008/010-008/010
VI. Geomagnetic Activity Probabilities 17 Sep to 19 Sep
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 20% | 20% | 20% |
| Minor storm | 10% | 10% | 10% |
| Major-severe storm | 01% | 01% | 01% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 30% | 25% | 25% |
| Minor storm | 15% | 10% | 10% |
| Major-severe storm | 05% | 01% | 01% |
All times in UTC
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