Viewing archive of Saturday, 21 April 2007

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 2007 Apr 21 2203 UTC
Prepared by the NOAA © SWPC and processed by SpaceWeatherLive.com

Joint USAF/NOAA Report of Solar and Geophysical Activity

SDF Number 111 Issued at 2200Z on 21 Apr 2007

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

Solar activity was very low. The visible solar disk remains spotless.
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 quiet.
IIB. Geophysical Activity Forecast
The geomagnetic field is expected to be quiet to unsettled with possible active periods at high latitudes on 22 April due to a recurrent coronal hole high speed stream. Expect quiet to unsettled conditions on 23 - 24 April.
III. Event Probabilities 22 Apr to 24 Apr
Class M01%01%01%
Class X01%01%01%
Proton01%01%01%
PCAFGreen
IV. Penticton 10.7 cm Flux
  Observed       21 Apr 069
  Predicted   22 Apr-24 Apr  070/070/070
  90 Day Mean        21 Apr 075
V. Geomagnetic A Indices
  Observed Afr/Ap 20 Apr  002/003
  Estimated     Afr/Ap 21 Apr  005/010
  Predicted    Afr/Ap 22 Apr-24 Apr  010/015-008/008-005/005
VI. Geomagnetic Activity Probabilities 22 Apr to 24 Apr
A. Middle Latitudes
Active25%20%15%
Minor storm10%10%05%
Major-severe storm01%01%01%
B. High Latitudes
Active35%25%25%
Minor storm20%15%15%
Major-severe storm05%01%01%

All times in UTC

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