Viewing archive of Wednesday, 21 July 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 Jul 21 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 203 Issued at 2200Z on 21 Jul 2004IA. Analysis of Solar Active Regions and Activity from 20-2100Z to 21-2100Z
Solar activity has been low. Region 649 (S10W41)
produced a C6.6/1f at 21/0034 UTC. Region 652 produced several
C-class flares, including a C8.9/1f at 21/0521 UTC. Region 649 was
stable in size and decreased in magnetic complexity to a beta-gamma
configuration. Region 652 increased signficantly in size over the
period, to 2010 millionths in white light, although most of the
growth was observed in the trailing penumbral field. The region's
magnetic class continues to be beta-gamma-delta, but all of the
magnetic complexity is in the northern part of the leader spots. No
new regions were numbered on the visible disk.
IB. Solar Activity Forecast
Solar activity is expected to be
predominantly moderate. However, there is still a possibility for
major flare activity from Region 652.
IIA. Geophysical Activity Summary 20-2100Z to 21-2100Z
The geomagnetic field has been quiet to unsettled.
IIB. Geophysical Activity Forecast
The geomagnetic field is
expected to be quiet to unsettled tomorrow (22 July), with active to
minor storm conditions expected on day two (23 July) from the
possible effects of a CME observed on LASCO imagery on 20 July.
Geomagnetic activity should return to quiet to unsettled conditions
on 24 July.
III. Event Probabilities 22 Jul to 24 Jul
| Class M | 65% | 65% | 65% |
| Class X | 20% | 20% | 20% |
| Proton | 10% | 10% | 15% |
| PCAF | green | ||
IV. Penticton 10.7 cm Flux
Observed 21 Jul 172 Predicted 22 Jul-24 Jul 175/170/160 90 Day Mean 21 Jul 101
V. Geomagnetic A Indices
Observed Afr/Ap 20 Jul 008/009 Estimated Afr/Ap 21 Jul 005/007 Predicted Afr/Ap 22 Jul-24 Jul 010/010-025/025-010/015
VI. Geomagnetic Activity Probabilities 22 Jul to 24 Jul
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 20% | 40% | 20% |
| Minor storm | 10% | 25% | 15% |
| Major-severe storm | 05% | 15% | 05% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 25% | 40% | 30% |
| Minor storm | 15% | 30% | 20% |
| Major-severe storm | 10% | 20% | 10% |
All times in UTC
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