Viewing archive of Monday, 21 April 2008

Solar activity report

Report of Solar-Geophysical Activity 2008 Apr 21 2203 UTC
Prepared by the NOAA © SWPC and processed by

Joint USAF/NOAA Report of Solar and Geophysical Activity

SDF Number 112 Issued at 2200Z on 21 Apr 2008

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

Solar activity was very low. No flares occurred during the past 24 hours. The solar disk is void of spots.
IB. Solar Activity Forecast
Solar activity is expected to be very low.
IIA. Geophysical Activity Summary 20-2100Z to 21-2100Z
The geomagnetic field was mostly quiet during the past 24 hours.
IIB. Geophysical Activity Forecast
The geomagnetic field is expected be quiet for most of the first day (22 April). However, an increase to unsettled with a chance for isolated active periods is expected late on the first day (22 April) or early on the second day (23 April) with the onset of a high speed solar wind stream. Unsettled levels with occasional active periods are expected to persist for the second and third days (23-24 April).
III. Event Probabilities 22 Apr to 24 Apr
Class M 01%01%01%
Class X 01%01%01%
IV. Penticton 10.7 cm Flux
  Observed       21 Apr 071
  Predicted    22 Apr-24 Apr  075/075/075
  90 Day Mean        21 Apr 072
V. Geomagnetic A Indices
  Observed Afr/Ap 20 Apr  001/004
  Estimated     Afr/Ap 21 Apr  005/005
  Predicted     Afr/Ap 22 Apr-24 Apr  008/008-015/015-012/012
VI. Geomagnetic Activity Probabilities 22 Apr to 24 Apr
A. Middle Latitudes
Minor storm 10%15%15%
Major-severe storm 05%05%05%
B. High Latitudes
Minor storm 15%20%20%
Major-severe storm 05%10%10%

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