Report of Solar-Geophysical Activity

Issued: 2005 Oct 25 2200 UTC

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

Joint USAF/NOAA Report of Solar and Geophysical Activity SDF Number 298 Issued at 2200Z on 25 Oct 2005 IA. Analysis of Solar Active Regions and Activity from 24/2100Z to 25/2100Z: Solar activity was at very low levels. No sunspots were reported on the visible disk. No new regions were numbered today.

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

IIA. Geophysical Activity Summary 24/2100Z to 25/2100Z:

The geomagnetic field was at quiet to active levels. A solar sector boundary crossing was observed at ACE at 24/2000 UTC. Solar wind speed is elevated at approximately 450 km/s due to a geoeffective coronal hole high speed wind stream.

IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be at quiet to unsettled levels. Isolated active conditions are possible due to the ongoing effects of a coronal hole high speed stream.

III. Event Probabilities 26 Oct-28 Oct

Class M 01/01/01

Class X 01/01/01

Proton 01/01/01

PCAF green

IV. Penticton 10.7 cm Flux

Observed 25 Oct 073

Predicted 26 Oct-28 Oct 075/075/075

90 Day Mean 25 Oct 088

V. Geomagnetic A Indices

Observed Afr/Ap 24 Oct 003/004

Estimated Afr/Ap 25 Oct 012/020

Predicted Afr/Ap 26 Oct-28 Oct 008/010-005/008-008/008 VI. Geomagnetic Activity Probabilities 26 Oct-28 Oct A. Middle Latitudes

Active 20/15/20

Minor storm 05/05/05

Major-severe storm 01/01/01

B. High Latitudes

Active 20/20/20

Minor storm 10/10/10

Major-severe storm 01/01/01