Viewing archive of Monday, 16 April 2001

Solar activity report

Report of Solar-Geophysical Activity 2001 Apr 16 2200 UTC
Prepared by the NOAA © SWPC and processed by

Joint USAF/NOAA Report of Solar and Geophysical Activity

SDF Number 106 Issued at 2200Z on 16 Apr 2001

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

Solar activity was moderate. An optically uncorrelated M1 event occurred at 16/0622 UTC. New Region 9430 (S16W33) was numbered today.
IB. Solar Activity Forecast
Solar activity is expected to be low to moderate.
IIA. Geophysical Activity Summary 15-2100Z to 16-2100Z
The geomagnetic field was quiet to unsettled. The greater than 10 MeV and greater than 100 MeV proton events that started yesterday are still in progress. Peak flux for the greater than 10 MeV protons was 951 pfu at 15/1920 UTC and the peak flux for the greater than 100 MeV was 146 pfu at 15/1525 UTC. The greater than 2 MeV electrons at geosynchronous orbit were at high levels and remained above threshold through the period. The polar cap absorption (PCA) event that started yesterday is still in progress.
IIB. Geophysical Activity Forecast
The geomagnetic field is expected to be unsettled to active for April 17. Active to minor storm conditions are expected for April 18 as a result of the X14/2b flare on April 15, and possible effects from a well positioned coronal hole. Unsettled to active conditions are expected to return on April 19. The greater than 10 MeV proton event is expected to continue for most of the period, and the greater than 100 MeV proton event is expected to go below threshold sometime on April 17.
III. Event Probabilities 17 Apr to 19 Apr
Class M70%60%50%
Class X25%10%10%
PCAFin progress
IV. Penticton 10.7 cm Flux
  Observed       16 Apr 123
  Predicted   17 Apr-19 Apr  130/140/150
  90 Day Mean        16 Apr 165
V. Geomagnetic A Indices
  Observed Afr/Ap 15 Apr  009/013
  Estimated     Afr/Ap 16 Apr  010/012
  Predicted    Afr/Ap 17 Apr-19 Apr  015/020-020/035-015/030
VI. Geomagnetic Activity Probabilities 17 Apr to 19 Apr
A. Middle Latitudes
Minor storm05%10%05%
Major-severe storm01%05%01%
B. High Latitudes
Minor storm10%15%15%
Major-severe storm05%10%10%

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