Viewing archive of Friday, 4 October 2002
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 2002 Oct 04 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 277 Issued at 2200Z on 04 Oct 2002IA. Analysis of Solar Active Regions and Activity from 03-2100Z to 04-2100Z Solar activity reached high levels. A total of five
M-class flares were observed this period. Region 137 (S19W20) was
the primary source for this activity, producing four M-class flares,
the largest being an M4/1n at 04/0538Z. A delta configuration was
observed to develop in this region late yesterday, and the region
exhibited frequent flare activity since. Region 139 appears to be
growing quickly as it rotates into view. This region produced an
M1/1f flare with associated Type II sweep (357 km/s) at 04/1255Z,
and also produced several moderate C-class flares. A delta
configuration is obvious and white light areal coverage is nearing
500 millionths. New Region 140 (S07E76) was numbered today.
IB. Solar Activity Forecast
Solar activity is expected to be at
moderate to high levels. Complex Regions 137 and 139 will continue
to produce M-class activity, with increasing likelihood for a major
flare from Region 139 as it continues to develop.
IIA. Geophysical Activity Summary 03-2100Z to 04-2100Z
The geomagnetic field was at predominantly active to major storm
levels with an isolated severe storm period between 04/00 - 03Z.
Though solar wind speed remains below 450 km/s, the Bz component of
the interplanetary magnetic field was sustained southward for the
entire period, ranging from -2 to -12 nT. The storm was gradually
subsiding by the end of the period.
IIB. Geophysical Activity Forecast
The geomagnetic field is
expected to range from unsettled to minor storm levels with isolated
major storm periods possible. Transient effects from CMEs observed
early on 3 Oct and again on 4 Oct will likely enhance the disturbed
periods on days two and three. A large, recurrent southern coronal
hole will move into geoeffective position late on day three.
III. Event Probabilities 05 Oct to 07 Oct
| Class M | 60% | 60% | 60% |
| Class X | 10% | 10% | 10% |
| Proton | 05% | 05% | 05% |
| PCAF | green | ||
IV. Penticton 10.7 cm Flux
Observed 04 Oct 158 Predicted 05 Oct-07 Oct 160/170/180 90 Day Mean 04 Oct 179
V. Geomagnetic A Indices
Observed Afr/Ap 03 Oct 022/033 Estimated Afr/Ap 04 Oct 035/045 Predicted Afr/Ap 05 Oct-07 Oct 018/020-015/020-012/015
VI. Geomagnetic Activity Probabilities 05 Oct to 07 Oct
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 50% | 50% | 40% |
| Minor storm | 25% | 25% | 20% |
| Major-severe storm | 15% | 15% | 05% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 50% | 50% | 50% |
| Minor storm | 30% | 30% | 30% |
| Major-severe storm | 20% | 20% | 20% |
All times in UTC
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