Viewing archive of Monday, 20 December 2004
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 2004 Dec 20 2200 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 20 Dec 2004IA. Analysis of Solar Active Regions and Activity from 19-2100Z to 20-2100Z Solar activity was very low. Region 713 (S09E34) has
grown in white light area coverage to over 200 millionths and has
developed a magnetic beta-gamma configuration. No new regions were
numbered today.
IB. Solar Activity Forecast
Solar activity is expected to be very
low to low. Region 713 could possibly produce an isolated C-class
event.
IIA. Geophysical Activity Summary 19-2100Z to 20-2100Z
The geomagnetic field was quiet. The greater than 2 MeV electron
flux at geosynchronous orbit was at high levels.
IIB. Geophysical Activity Forecast
The geomagnetic field is
expected to be quiet to unsettled. Isolated active periods are
possible on 22 December due to the influence of a recurrent coronal
hole high speed solar wind stream.
III. Event Probabilities 21 Dec to 23 Dec
| Class M | 15% | 15% | 15% |
| Class X | 01% | 01% | 01% |
| Proton | 01% | 01% | 01% |
| PCAF | Green | ||
IV. Penticton 10.7 cm Flux
Observed 20 Dec 094 Predicted 21 Dec-23 Dec 100/100/105 90 Day Mean 20 Dec 104
V. Geomagnetic A Indices
Observed Afr/Ap 19 Dec 001/004 Estimated Afr/Ap 20 Dec 003/004 Predicted Afr/Ap 21 Dec-23 Dec 008/010-015/020-010/012
VI. Geomagnetic Activity Probabilities 21 Dec to 23 Dec
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 15% | 25% | 20% |
| Minor storm | 05% | 10% | 10% |
| Major-severe storm | 01% | 05% | 01% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 20% | 30% | 25% |
| Minor storm | 10% | 20% | 15% |
| Major-severe storm | 05% | 05% | 05% |
All times in UTC
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