Viewing archive of Tuesday, 31 July 2001

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 2001 Jul 31 2200 UTC
Prepared by the NOAA © SWPC and processed by

Joint USAF/NOAA Report of Solar and Geophysical Activity

SDF Number 212 Issued at 2200Z on 31 Jul 2001

IA. Analysis of Solar Active Regions and Activity from 30-2100Z to 31-2100Z

Solar activity remained low. Isolated B- and C-class subflares occurred. Region 9561 (S12E49) was the most active of the visible regions, but showed no significant changes during the period. A couple large filaments erupted from the south-central portion of the disk early in the period. New Region 9563 (N24E57) was numbered.
IB. Solar Activity Forecast
Solar activity is expected to remain at low levels.
IIA. Geophysical Activity Summary 30-2100Z to 31-2100Z
Geomagnetic field activity was at unsettled to active levels due to coronal hole effects.
IIB. Geophysical Activity Forecast
Geomagnetic field activity is expected to be at quiet to active levels on the first day decreasing to quiet to unsettled levels for the remainder of the period.
III. Event Probabilities 01 Aug to 03 Aug
Class M20%20%20%
Class X01%01%01%
IV. Penticton 10.7 cm Flux
  Observed       31 Jul 117
  Predicted   01 Aug-03 Aug  120/120/125
  90 Day Mean        31 Jul 150
V. Geomagnetic A Indices
  Observed Afr/Ap 30 Jul  008/009
  Estimated     Afr/Ap 31 Jul  018/023
  Predicted    Afr/Ap 01 Aug-03 Aug  012/015-008/010-008/010
VI. Geomagnetic Activity Probabilities 01 Aug to 03 Aug
A. Middle Latitudes
Minor storm15%10%10%
Major-severe storm05%01%01%
B. High Latitudes
Minor storm20%15%15%
Major-severe storm05%01%01%

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