Viewing archive of Wednesday, 11 September 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 Sep 11 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 254 Issued at 2200Z on 11 Sep 2002IA. Analysis of Solar Active Regions and Activity from 10-2100Z to 11-2100Z Solar activity has been moderate. Region 105 (S09E28)
produced the largest event of the period, an M2/2b flare at 11/0735
UTC with an associated tenflare (230 sfu). Region 107 (N11E30) was
a source of several C-class flares during the period, and Region 100
(S19W64) also produced a C-class flare. Region 103 (N14W33) has
remained quiescent, but appears somewhat more compact today and
retains moderate magnetic complexity.
IB. Solar Activity Forecast
Solar activity is expected to be at
moderate levels for the next three days. Region 105 is a likely
source of further M-class activity. Regions 103 and 107 may become
more active during the period and could produce M-class flares as
well.
IIA. Geophysical Activity Summary 10-2100Z to 11-2100Z
Geomagnetic field conditions have ranged from quiet to major storm
levels. Onset of coronal hole high speed stream effects have been
evident since about 11/0900 UTC, and the single period of major
storm conditions observed at higher latitudes occurred shortly
thereafter. The remainder of the day had conditions in the
unsettled to minor storm range.
IIB. Geophysical Activity Forecast
The geomagnetic field is
expected to be mainly unsettled to active for the next 24-48 hours.
Isolated minor storm conditions may also occur, especially at higher
latitudes. Conditions are expected to be in the quiet to unsettled
range by the end of the forecast period.
III. Event Probabilities 12 Sep to 14 Sep
| Class M | 65% | 65% | 65% |
| Class X | 10% | 10% | 10% |
| Proton | 05% | 05% | 05% |
| PCAF | green | ||
IV. Penticton 10.7 cm Flux
Observed 11 Sep 216 Predicted 12 Sep-14 Sep 220/220/225 90 Day Mean 11 Sep 173
V. Geomagnetic A Indices
Observed Afr/Ap 10 Sep 014/024 Estimated Afr/Ap 11 Sep 020/025 Predicted Afr/Ap 12 Sep-14 Sep 018/018-015/018-012/015
VI. Geomagnetic Activity Probabilities 12 Sep to 14 Sep
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 35% | 30% | 25% |
| Minor storm | 10% | 10% | 05% |
| Major-severe storm | 05% | 01% | 01% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 35% | 35% | 30% |
| Minor storm | 15% | 15% | 10% |
| Major-severe storm | 05% | 05% | 01% |
All times in UTC
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