Viewing archive of Friday, 21 December 2007
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 2007 Dec 21 2203 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 355 Issued at 2200Z on 21 Dec 2007IA. Analysis of Solar Active Regions and Activity from 20-2100Z to 21-2100Z
Solar activity was very low. The visible disk remains
spotless.
IB. Solar Activity Forecast
Solar activity is expected to be very
low.
IIA. Geophysical Activity Summary 20-2100Z to 21-2100Z
The geomagnetic field was quiet to unsettled. Solar wind
observations at ACE gradually decreased in velocity from a high of
745 km/s at 20/2128Z to 600 km/s at forecast issue time. The
greater than 2 MeV electron flux at geosynchronous orbit reached
high levels today.
IIB. Geophysical Activity Forecast
The geomagnetic field is
expected to be quiet to unsettled for the next three days (22-24
December). Isolated active conditions are possible at high
latitudes for days 1 and 2 (22-23 December).
III. Event Probabilities 22 Dec to 24 Dec
| Class M | 01% | 01% | 01% |
| Class X | 01% | 01% | 01% |
| Proton | 01% | 01% | 01% |
| PCAF | Green | ||
IV. Penticton 10.7 cm Flux
Observed 21 Dec 071 Predicted 22 Dec-24 Dec 070/069/069 90 Day Mean 21 Dec 071
V. Geomagnetic A Indices
Observed Afr/Ap 20 Dec 010/012 Estimated Afr/Ap 21 Dec 008/012 Predicted Afr/Ap 22 Dec-24 Dec 008/010-006/008-005/005
VI. Geomagnetic Activity Probabilities 22 Dec to 24 Dec
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 15% | 15% | 15% |
| Minor storm | 05% | 01% | 01% |
| Major-severe storm | 01% | 01% | 01% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 30% | 20% | 15% |
| Minor storm | 10% | 05% | 05% |
| Major-severe storm | 05% | 01% | 01% |
All times in UTC
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