Viewing archive of Tuesday, 18 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 18 2200 UTC
Prepared by the NOAA © SWPC and processed by

Joint USAF/NOAA Report of Solar and Geophysical Activity

SDF Number 352 Issued at 2200Z on 18 Dec 2001

IA. Analysis of Solar Active Regions and Activity from 17-2100Z to 18-2100Z

Solar activity was at low levels. Only isolated C-class events were observed during the period. Three regions have moderately complex beta-gamma magnetic classification: 9733 (N13W62), 9738 (S18W12), and 9742 (N10E37). Regions 9738 and 9742 are showing signs of increased activity and growth, while 9733 is steadily decaying. Region 9733 will rotate over the west limb on 21 December. One new region was numbered: 9745 (N18E60).
IB. Solar Activity Forecast
Solar activity is expected to be at low to moderate levels. Regions 9738 and 9742 are expected to continue to grow in size and complexity and should produce increased levels of activity. Region 9733 continues to retain a slight chance of producing a major flare before it transits over the western limb.
IIA. Geophysical Activity Summary 17-2100Z to 18-2100Z
The geomagnetic field was at quiet to unsettled conditions.
IIB. Geophysical Activity Forecast
The geomagnetic field is expected to continue to be at quiet to unsettled levels.
III. Event Probabilities 19 Dec to 21 Dec
Class M75%75%75%
Class X10%10%10%
IV. Penticton 10.7 cm Flux
  Observed       18 Dec 212
  Predicted   19 Dec-21 Dec  200/200/195
  90 Day Mean        18 Dec 219
V. Geomagnetic A Indices
  Observed Afr/Ap 17 Dec  009/015
  Estimated     Afr/Ap 18 Dec  008/008
  Predicted    Afr/Ap 19 Dec-21 Dec  008/008-008/008-008/008
VI. Geomagnetic Activity Probabilities 19 Dec to 21 Dec
A. Middle Latitudes
Minor storm05%05%05%
Major-severe storm01%01%01%
B. High Latitudes
Minor storm10%10%10%
Major-severe storm01%01%01%

All times in UTC

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