Joint USAF/NOAA Report of Solar and Geophysical Activity 24 May 2005

Prepared jointly by the U.S. Dept. of Commerce, NOAA,
Space Environment Center and the U.S. Air Force.
Updated 2005 May 24 2210 UTC

Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 144 Issued at 2200Z on 24 May 2005

IA. Analysis of Solar Active Regions and Activity from 23/2100Z
to 24/2100Z: Solar activity continued at very low levels. Region 767
(S08E40) is in a slow growth phase and produced occasional B-class
flares. Region 766 (N13E37), the only other sunspot group on the
visible disk, was stable.

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 23/2100Z to 24/2100Z:
The geomagnetic field was quiet. Solar wind speed declined to below
400 km/s.

IIB. Geophysical Activity Forecast: The geomagnetic field is
expected to be quiet with occasional unsettled periods on 25 and 26
May. A recurrent coronal hole high speed stream is expected to
rotate into geoeffective position on 27 May, and produce occasional
active periods.

III. Event Probabilities 25 May-27 May

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

IV. Penticton 10.7 cm Flux

• Observed 24 May 085
• Predicted 25 May-27 May 085/085/085
• 90 Day Mean 24 May 091

V. Geomagnetic A Indices

• Observed Afr/Ap 23 May 005/007
• Estimated Afr/Ap 24 May 005/005
• Predicted Afr/Ap 25 May-27 May 005/008-005/010-010/015

VI. Geomagnetic Activity Probabilities 25 May-27 May

A. Middle Latitudes

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

B. High Latitudes

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