Joint USAF/NOAA Report of Solar and Geophysical Activity 02 Oct 2005

Prepared jointly by the U.S. Dept. of Commerce, NOAA,
Space Environment Center and the U.S. Air Force.
Updated 2005 Oct 02 2204 UTC

Joint USAF/NOAA Report of Solar and Geophysical Activity SDF Number 275 Issued at 2200Z on 02 Oct 2005

IA. Analysis of Solar Active Regions and Activity from 01/2100Z to 02/2100Z: Solar activity was very low.

IB. Solar Activity Forecast: Solar activity is expected to be very low on 03 October. Activity is expected to increase to low levels with isolated M-flares possible on 04 and 05 October due to the return of old Region 808 (S09, L=232). Region 808 produced a total of 13 major flares (M5 or greater) during its last transit across the visible disk.

IIA. Geophysical Activity Summary 01/2100Z to 02/2100Z: The geomagnetic field was quiet to active. Active periods were due to extended intervals of southward Bz. The greater than 2 MeV electron flux at geosynchronous orbit reached high levels today.

IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be quiet to unsettled with isolated active periods possible.

III. Event Probabilities 03 Oct-05 Oct

• Class M 10/25/25
• Class X 01/05/05
• Proton 01/01/05
• PCAF Green

IV. Penticton 10.7 cm Flux

• Observed 02 Oct 075
• Predicted 03 Oct-05 Oct 080/085/090
• 90 Day Mean 02 Oct 091

V. Geomagnetic A Indices

• Observed Afr/Ap 01 Oct 010/013
• Estimated Afr/Ap 02 Oct 008/010
• Predicted Afr/Ap 03 Oct-05 Oct 008/010-008/010-008/010

VI. Geomagnetic Activity Probabilities 03 Oct-05 Oct

A. Middle Latitudes

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

B. High Latitudes

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