Viewing archive of Thursday, 20 September 2001
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 2001 Sep 20 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 263 Issued at 2200Z on 20 Sep 2001IA. Analysis of Solar Active Regions and Activity from 19-2100Z to 20-2100Z Solar activity was at moderate levels. A M1.5/Sn
occurred in new Region 9631 (N08W15) which has been active since
its emergence. Six C-class flares also occurred during the period,
the largest a C7.8 in Region 9628 (S18E51). Region 9628 has
increased in magnetic complexity to a Beta-Gamma and increased in
spot count. Region 9620 (N12E17) has also increased in magnetic
complexity to a Beta-Gamma. New Region 9630 (N27W36) and Region
9632 (S18E76) were also numbered today.
IB. Solar Activity Forecast
Solar activity is expected to be low
to moderate. Region 9628 and Region 9620 are becoming more complex
and could produce M-class flares.
IIA. Geophysical Activity Summary 19-2100Z to 20-2100Z
Geomagnetic activity was quiet to unsettled.
IIB. Geophysical Activity Forecast
Geomagnetic activity is
expected to be quiet to unsettled. Isolated active conditions may
occur early in the period due to a CME observed on 18 SEP O1.
III. Event Probabilities 21 Sep to 23 Sep
| Class M | 80% | 80% | 80% |
| Class X | 10% | 10% | 10% |
| Proton | 05% | 05% | 05% |
| PCAF | green | ||
IV. Penticton 10.7 cm Flux
Observed 20 Sep 227 Predicted 21 Sep-23 Sep 230/230/230 90 Day Mean 20 Sep 165
V. Geomagnetic A Indices
Observed Afr/Ap 19 Sep 008/008 Estimated Afr/Ap 20 Sep 008/008 Predicted Afr/Ap 21 Sep-23 Sep 012/015-012/012-010/010
VI. Geomagnetic Activity Probabilities 21 Sep to 23 Sep
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 25% | 20% | 20% |
| Minor storm | 15% | 10% | 05% |
| Major-severe storm | 05% | 01% | 01% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 30% | 25% | 25% |
| Minor storm | 20% | 15% | 10% |
| Major-severe storm | 05% | 01% | 01% |
All times in UTC
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