Viewing archive of Thursday, 16 September 2004

Solar activity report

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

Joint USAF/NOAA Report of Solar and Geophysical Activity

SDF Number 260 Issued at 2200Z on 16 Sep 2004

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

Solar activity has been very low. Region 672 (N05W17) produced a B8.7/Sf at 16/0030 UTC and a B8.4/Sf at 0345 UTC. Region 672 has decayed slightly but has maintained a beta-delta magnetic configuration. Region 673 (S12E61) is in better view for observation and, with trailer spots behind a larger lead spot, is in a beta-gamma configuration. No new regions were numbered today.
IB. Solar Activity Forecast
Solar activity is expected to be low. Regions 672 and 673 may produce C-class flares. Both regions are capable of isolated M-class flares as well.
IIA. Geophysical Activity Summary 15-2100Z to 16-2100Z
The geomagnetic field has been quiet to active. There has been a slight rise in solar wind speed at ACE since 1600 UTC, to about 550 km/s at the end of the period. The greater than 2 MeV electron flux at geosynchronous orbit reached high levels today.
IIB. Geophysical Activity Forecast
The geomagnetic field is expected to be unsettled to active for 17 September, from the effects of increased solar winds from a geoeffective coronal hole. Activity should subside for 18-19 September to quiet to unsettled levels.
III. Event Probabilities 17 Sep to 19 Sep
Class M25%25%25%
Class X05%05%05%
IV. Penticton 10.7 cm Flux
  Observed       16 Sep 108
  Predicted   17 Sep-19 Sep  110/110/110
  90 Day Mean        16 Sep 112
V. Geomagnetic A Indices
  Observed Afr/Ap 15 Sep  009/014
  Estimated     Afr/Ap 16 Sep  020/018
  Predicted    Afr/Ap 17 Sep-19 Sep  015/020-010/015-010/010
VI. Geomagnetic Activity Probabilities 17 Sep to 19 Sep
A. Middle Latitudes
Minor storm10%05%05%
Major-severe storm01%01%01%
B. High Latitudes
Minor storm30%25%25%
Major-severe storm10%10%05%

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