Viewing archive of Thursday, 17 May 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 May 17 2203 UTC
Prepared by the NOAA © SWPC and processed by

Joint USAF/NOAA Report of Solar and Geophysical Activity

SDF Number 137 Issued at 2200Z on 17 May 2007

IA. Analysis of Solar Active Regions and Activity from 16-2100Z to 17-2100Z

Solar activity decreased to very low levels. Region 956 (N02E21) was limited to the production of multiple B-class flares during the past 24 hours. The sunspot area and magnetic complexity underwent further enhancement today. Region analysis continues to depict a Dkc beta-gamma-delta sunspot group. Regions 955 (S09W92) and 957 (S04W47) were spotless over the past 24 hours. No new regions were numbered today.
IB. Solar Activity Forecast
Solar activity is expected to be at low levels. There is a slight chance of an isolated M-class flare from Region 956.
IIA. Geophysical Activity Summary 16-2100Z to 17-2100Z
The geomagnetic field was at predominantly quiet levels.
IIB. Geophysical Activity Forecast
The geomagnetic field is expected to be at predominantly quiet levels on 17 May. Predominantly unsettled to active conditions with isolated minor storm periods are possible on 19 and 20 May, due to a recurrent coronal hole high speed stream.
III. Event Probabilities 18 May to 20 May
Class M25%25%25%
Class X05%05%05%
IV. Penticton 10.7 cm Flux
  Observed       17 May 077
  Predicted   18 May-20 May  075/075/075
  90 Day Mean        17 May 074
V. Geomagnetic A Indices
  Observed Afr/Ap 16 May  003/004
  Estimated     Afr/Ap 17 May  005/005
  Predicted    Afr/Ap 18 May-20 May  005/005-010/010-010/020
VI. Geomagnetic Activity Probabilities 18 May to 20 May
A. Middle Latitudes
Minor storm01%10%10%
Major-severe storm01%05%05%
B. High Latitudes
Minor storm05%15%25%
Major-severe storm01%05%15%

All times in UTC

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