Viewing archive of Monday, 21 December 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 Dec 21 2201 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 2009IA. Analysis of Solar Active Regions and Activity from 20-2100Z to 21-2100Z Solar activity was low. Isolated low-level C-class
flares and occasional B-class flares were observed. Region 1035
(N31W85) showed no significant change as it approached the west
limb. Region 1036 (S27W45) showed rapid growth and was classified as
a Dso/Beta at the end of the period. No new regions were numbered.
IB. Solar Activity Forecast
Solar activity is expected to be low.
Isolated C-class flare activity is expected. There is also a slight
chance for an isolated M-class flare.
IIA. Geophysical Activity Summary 20-2100Z to 21-2100Z
Geomagnetic field activity was at quiet levels.
IIB. Geophysical Activity Forecast
Geomagnetic field activity is
expected to be at quiet levels through the period (22 - 24
December).
III. Event Probabilities 22 Dec to 24 Dec
| Class M | 10% | 05% | 05% |
| Class X | 01% | 01% | 01% |
| Proton | 01% | 01% | 01% |
| PCAF | Green | ||
IV. Penticton 10.7 cm Flux
Observed 21 Dec 083 Predicted 22 Dec-24 Dec 080/076/074 90 Day Mean 21 Dec 074
V. Geomagnetic A Indices
Observed Afr/Ap 20 Dec 002/001 Estimated Afr/Ap 21 Dec 001/005 Predicted Afr/Ap 22 Dec-24 Dec 005/005-005/005-005/005
VI. Geomagnetic Activity Probabilities 22 Dec to 24 Dec
| 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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