Status Report

Joint USAF/NOAA Report of Solar and Geophysical Activity 25 May 2005

By SpaceRef Editor
May 25, 2005
Filed under , ,

Prepared jointly by the U.S. Dept. of Commerce, NOAA,
Space Environment Center and the U.S. Air Force.
Updated 2005 May 25 2210 UTC

Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 145 Issued at 2200Z on 25 May 2005

IA. Analysis of Solar Active Regions and Activity from 24/2100Z
to 25/2100Z: Solar activity continues at very low levels. Occasional
B-class flares were observed in Regions 766 (N14E23) and 767
(S07E26). These two active regions are the only sunspot groups on
the visible disk, and exhibited little change this period. A large
CME off the east limb was observed on LASCO imagery during the
latter half of 24 May. The likely source of this CME was backsided.

IB. Solar Activity Forecast: Solar activity is expected to continue
at very low levels. There is a slight chance for a C-class flare
from Region 767.

IIA. Geophysical Activity Summary 24/2100Z to 25/2100Z:
The geomagnetic field was quiet. Solar wind speed declined to near
360 km/s. The greater than 2 MeV electron flux at geosynchronous
orbit was at high levels.

IIB. Geophysical Activity Forecast: The geomagnetic field is
expected to be quiet, with isolated unsettled periods on 26 May.
Occasional active periods are expected on 27 and 28 May as a coronal
hole high speed stream rotates into a geoeffective position.

III. Event Probabilities 26 May-28 May

  • Class M 05/05/05
  • Class X 01/01/01
  • Proton 01/01/01
  • PCAF green

IV. Penticton 10.7 cm Flux

  • Observed 25 May 084
  • Predicted 26 May-28 May 085/085/095
  • 90 Day Mean 25 May 090

V. Geomagnetic A Indices

  • Observed Afr/Ap 24 May 002/005
  • Estimated Afr/Ap 25 May 005/005
  • Predicted Afr/Ap 26 May-28 May 005/010-010/015-015/020

VI. Geomagnetic Activity Probabilities 26 May-28 May

A. Middle Latitudes

  • Active 15/20/30
  • Minor storm 05/10/15
  • Major-severe storm 01/01/05

B. High Latitudes

  • Active 20/40/50
  • Minor storm 10/20/25
  • Major-severe storm 01/05/10

SpaceRef staff editor.