Viewing archive of Friday, 16 April 2004

Solar activity report

Report of Solar-Geophysical Activity 2004 Apr 16 2200 UTC
Prepared by the NOAA © SWPC and processed by

Joint USAF/NOAA Report of Solar and Geophysical Activity

SDF Number 107 Issued at 2200Z on 16 Apr 2004

IA. Analysis of Solar Active Regions and Activity from 15-2100Z to 16-2100Z

Solar activity was at very low levels. The largest flare of the period was a B8 from newly numbered Region 595(S09E68). Region 591(S16W52) continues to show signs of decay but still has some weak polarity mixing.
IB. Solar Activity Forecast
Solar activity is expected to be very low to low. Region 591 and 595 have the potential for C-class activity.
IIA. Geophysical Activity Summary 15-2100Z to 16-2100Z
The geomagnetic field was at quiet to active levels. Two periods of active conditions were observed due to elevated wind speed and a weak coronal hole influence.
IIB. Geophysical Activity Forecast
The geomagnetic field is expected to be at quiet to unsettled levels with a chance of isolated active conditions due to elevated solar wind speeds.
III. Event Probabilities 17 Apr to 19 Apr
Class M05%05%05%
Class X01%01%01%
IV. Penticton 10.7 cm Flux
  Observed       16 Apr 097
  Predicted   17 Apr-19 Apr  100/100/100
  90 Day Mean        16 Apr 108
V. Geomagnetic A Indices
  Observed Afr/Ap 15 Apr  003/006
  Estimated     Afr/Ap 16 Apr  010/012
  Predicted    Afr/Ap 17 Apr-19 Apr  008/012-006/010-003/008
VI. Geomagnetic Activity Probabilities 17 Apr to 19 Apr
A. Middle Latitudes
Minor storm05%05%05%
Major-severe storm01%01%01%
B. High Latitudes
Minor storm10%10%05%
Major-severe storm01%01%01%

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