Viewing archive of Saturday, 18 August 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 Aug 18 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 230 Issued at 2200Z on 18 Aug 2001IA. Analysis of Solar Active Regions and Activity from 17-2100Z to 18-2100Z Solar activity was low. Several C-class flares
occurred, principally from Region 9582 (N28E33). The other main area
of note is Region 9585 (N15E50) which has grown considerably in
sunspot area and has increased its magnetic complexity.
IB. Solar Activity Forecast
Solar activity is expected to be low.
Additional C-class flares are possible in Regions 9582 and 9585. A
small chance of M-level activity also exists.
IIA. Geophysical Activity Summary 17-2100Z to 18-2100Z
The geomagnetic field remained at storm levels until about 18/0000
UTC and was mostly unsettled to active after that. The greater than
10 MeV solar energetic proton event continues to slowly decay and
has been fluctuating around the 10 pfu event threshold for most of
the day.
IIB. Geophysical Activity Forecast
The geomagnetic field is
expected to be unsettled to active becoming quiet to unsettled by
the second day of the forecast period. The greater than 10 MeV
proton event is expected to end by 19 August.
III. Event Probabilities 19 Aug to 21 Aug
| Class M | 10% | 10% | 10% |
| Class X | 01% | 01% | 01% |
| Proton | 01% | 01% | 01% |
| PCAF | green | ||
IV. Penticton 10.7 cm Flux
Observed 18 Aug 156 Predicted 19 Aug-21 Aug 160/165/170 90 Day Mean 18 Aug 151
V. Geomagnetic A Indices
Observed Afr/Ap 17 Aug 027/029 Estimated Afr/Ap 18 Aug 015/015 Predicted Afr/Ap 19 Aug-21 Aug 012/012-010/015-010/012
VI. Geomagnetic Activity Probabilities 19 Aug to 21 Aug
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 15% | 15% | 15% |
| Minor storm | 05% | 01% | 01% |
| Major-severe storm | 01% | 01% | 01% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 15% | 15% | 15% |
| Minor storm | 05% | 05% | 05% |
| Major-severe storm | 01% | 01% | 01% |
All times in UTC
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