Status Report

Joint USAF/NOAA Report of Solar and Geophysical Activity 31 Aug 2005

By SpaceRef Editor
September 1, 2005
Filed under , ,

Prepared jointly by the U.S. Dept. of Commerce, NOAA,
Space Environment Center and the U.S. Air Force.
Updated 2005 Aug 31 2203 UTC

Joint USAF/NOAA Report of Solar and Geophysical Activity 31 Aug 2005
SDF Number 243 Issued at 2200Z on 31 Aug 2005

IA. Analysis of Solar Active Regions and Activity from 30/2100Z
to 31/2100Z: Solar activity was at low levels. Region 803 (N11W13)
produced a long duration C2 x-ray event that occurred at 31/1151Z.
This event was followed by a full halo CME that was first observed
at 31/1100Z by LASCO imagery. Region 803 continues to show decay
and is down to 20 millionths of sunspot area. Region 806 (S17E23)
was limited to B-class flare activity and has shown slight decay in
sunspot coverage. The magnetic gamma structure remains intact
although it has weakened since yesterday. No new regions were
numbered today.

IB. Solar Activity Forecast: Solar activity is expected to be at
very low to low levels.

IIA. Geophysical Activity Summary 30/2100Z to 31/2100Z:
The geomagnetic field was at quiet to minor storm levels. The
elevated conditions ensued following a sustained southward Bz
(ranging between -10 and -20 nT) which began just after 31/1000Z.
This activity is believed to be in response to a corotating
interaction region. The greater than 2 MeV electron flux at
geosynchronous orbit reached high levels again today.

IIB. Geophysical Activity Forecast: The geomagnetic field is
expected to be at quiet to minor storm levels. A coronal hole may
keep conditions elevated throughout the period. Isolated major
storm conditions may be possible on 2 September due to the effects
of the full halo CME from the long duration C2 x-ray event that
occurred today.

III. Event Probabilities 01 Sep-03 Sep

  • Class M 15/15/15
  • Class X 01/01/01
  • Proton 01/01/01
  • PCAF green

IV. Penticton 10.7 cm Flux

  • Observed 31 Aug 084
  • Predicted 01 Sep-03 Sep 080/080/080
  • 90 Day Mean 31 Aug 094

V. Geomagnetic A Indices

  • Observed Afr/Ap 30 Aug 003/004
  • Estimated Afr/Ap 31 Aug 018/032
  • Predicted Afr/Ap 01 Sep-03 Sep 015/020-025/030-020/025

VI. Geomagnetic Activity Probabilities 01 Sep-03 Sep

A. Middle Latitudes

  • Active 30/45/35
  • Minor storm 15/25/20
  • Major-severe storm 05/15/10

B. High Latitudes

  • Active 35/40/40
  • Minor storm 20/30/25
  • Major-severe storm 10/20/15

SpaceRef staff editor.