Viewing archive of Thursday, 13 December 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 Dec 13 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 347 Issued at 2200Z on 13 Dec 2001IA. Analysis of Solar Active Regions and Activity from 12-2100Z to 13-2100Z Solar activity was high. Region 9733 (N14E04) produced
an X6.2/3b flare at 13/1430 UTC. This event also produced associated
Type II and IV radio sweeps and a partial-halo coronal mass ejection
(CME). This region is continuing to grow more complex, developing a
near horizontal inversion line in its trailing portions. Region 9727
(S21W66) was also quite active during the period, producing three
M-class flares. Region 9727 showed continued growth in size and
complexity during the period. Regions 9727 and 9733 both retain
beta-gamma-delta magnetic classifications. Three new spot groups
were numbered today: 9739 (S13W02), 9740 (S06E56), and 9741
(N07E72).
IB. Solar Activity Forecast
Solar activity is expected to be at
moderate to high levels with isolated M-class flares likely. There
will also be a chance for a major flare from Regions 9727 or 9733.
IIA. Geophysical Activity Summary 12-2100Z to 13-2100Z
The geomagnetic field was at mostly quiet levels, with an isolated
unsettled period at 12/21-2400 UTC.
IIB. Geophysical Activity Forecast
The geomagnetic field is
expected to be at quiet to unsettled conditions on the first day of
the forecast period. The CME produced by the X6.2 flare should
impact earth late on the second day. The impact is expected to
produce active conditions on the second and third days. Imagery from
the LASCO/SOHO spacecraft show that most of the CME is directed in a
predominately Northerly direction, hence the expected effect on
Earth should be significantly less than if the CME was more directly
aimed toward Earth.
III. Event Probabilities 14 Dec to 16 Dec
| Class M | 80% | 80% | 70% |
| Class X | 20% | 20% | 15% |
| Proton | 20% | 20% | 15% |
| PCAF | yellow | ||
IV. Penticton 10.7 cm Flux
Observed 13 Dec 220 Predicted 14 Dec-16 Dec 220/220/210 90 Day Mean 13 Dec 218
V. Geomagnetic A Indices
Observed Afr/Ap 12 Dec 008/012 Estimated Afr/Ap 13 Dec 006/007 Predicted Afr/Ap 14 Dec-16 Dec 012/015-020/020-025/025
VI. Geomagnetic Activity Probabilities 14 Dec to 16 Dec
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 20% | 30% | 40% |
| Minor storm | 10% | 20% | 25% |
| Major-severe storm | 01% | 10% | 15% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 25% | 40% | 45% |
| Minor storm | 15% | 25% | 30% |
| Major-severe storm | 05% | 10% | 10% |
All times in UTC
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