Viewing archive of Tuesday, 21 December 2004

Solar activity report

Report of Solar-Geophysical Activity 2004 Dec 21 2200 UTC
Prepared by the NOAA © SWPC and processed by

Joint USAF/NOAA Report of Solar and Geophysical Activity

SDF Number 356 Issued at 2200Z on 21 Dec 2004

IA. Analysis of Solar Active Regions and Activity from 20-2100Z to 21-2100Z

Solar activity has been very low. Region 713 (S08E22) has produced several B-class flares and retains its beta-gamma magnetic configuration.
IB. Solar Activity Forecast
Solar activity is expected to be very low to low. There is a chance for an isolated C-class event from Region 713.
IIA. Geophysical Activity Summary 20-2100Z to 21-2100Z
The geomagnetic field was quiet to unsettled with an isolated period of active to minor storm conditions observed at 21/1200 UTC. Solar wind data indicated a possible co-rotating interaction region signature during this period. Solar wind speed ranged from around 350 to 490 km/s with the IMF Bz fluctuating to -14 nT.
IIB. Geophysical Activity Forecast
The geomagnetic field is expected to be predominately quiet to unsettled with isolated periods of active conditions on 22-23 December due to coronal hole effects. Quiet to unsettled conditions are expected for 24 December.
III. Event Probabilities 22 Dec to 24 Dec
Class M20%20%20%
Class X01%01%01%
IV. Penticton 10.7 cm Flux
  Observed       21 Dec 101
  Predicted   22 Dec-24 Dec  100/105/105
  90 Day Mean        21 Dec 104
V. Geomagnetic A Indices
  Observed Afr/Ap 20 Dec  002/004
  Estimated     Afr/Ap 21 Dec  008/015
  Predicted    Afr/Ap 22 Dec-24 Dec  015/020-010/015-010/010
VI. Geomagnetic Activity Probabilities 22 Dec to 24 Dec
A. Middle Latitudes
Minor storm10%10%10%
Major-severe storm05%01%01%
B. High Latitudes
Minor storm20%15%15%
Major-severe storm05%05%01%

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