Status Report

Joint USAF/NOAA Report of Solar and Geophysical Activity 22 Oct 2004

By SpaceRef Editor
October 22, 2004
Filed under , ,

Prepared jointly by the U.S. Dept. of Commerce, NOAA,
Space Environment Center and the U.S. Air Force.

Updated 2004 Oct 22 2210 UTC

Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 296 Issued at 2200Z on 22 Oct 2004

IA. Analysis of Solar Active Regions and Activity from 21/2100Z
to 22/2100Z: Solar activity increased to moderate levels today.
Region 687 (N10E39) produced an M2/1n flare at 22/0811Z that had an
associated Type IV radio sweep and a Type II radio sweep with an
estimated shock velocity 521 km/sec. LASCO imagery depicted a CME
shortly following this event which may have a weak Earth-bound
component. The sunspot area in this region underwent strong growth
during the period, adding penumbral coverage to the trailing cluster
of spots in the group. Region 682 (S13W59) underwent little change
today and produced a single low level B-class flare. Region 684
(S05E01) has shown rapid growth in sunspot area and magnetic
structure during the period. Region 690 (N00E78) was numbered

IB. Solar Activity Forecast: Solar activity is expected to be at
low to moderate levels. Region 687 is capable of producing further
M-class flares and has a slight chance of producing an isolated
major flare.

IIA. Geophysical Activity Summary 21/2100Z to 22/2100Z:
The geomagnetic field was at quiet levels today.

IIB. Geophysical Activity Forecast: The geomagnetic field is
expected to be at quiet to unsettled levels on 23 and 24 October. A
chance of isolated active conditions may occur on 25 October due to
the potential for a glancing blow from the CME that resulted from
the M2/1n flare mentioned in IA.

III. Event Probabilities 23 Oct-25 Oct

  • Class M 50/50/50
  • Class X 01/01/01
  • Proton 01/01/01
  • PCAF Green

IV. Penticton 10.7 cm Flux

  • Observed 22 Oct 123
  • Predicted 23 Oct-25 Oct 125/130/125
  • 90 Day Mean 22 Oct 104

V. Geomagnetic A Indices

  • Observed Afr/Ap 21 Oct 005/008
  • Estimated Afr/Ap 22 Oct 004/005
  • Predicted Afr/Ap 23 Oct-25 Oct 004/005-005/005-010/010

VI. Geomagnetic Activity Probabilities 23 Oct-25 Oct

A. Middle Latitudes

  • Active 15/15/20
  • Minor storm 01/01/10
  • Major-severe storm 01/01/01

B. High Latitudes

  • Active 15/15/20
  • Minor storm 05/05/10
  • Major-severe storm 01/01/05

SpaceRef staff editor.