Joint USAF/NOAA Report of Solar and Geophysical Activity 01 Dec 2005

Product: Report of Solar-Geophysical Activity
Issued: 2005 Dec 01 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 335 Issued at 2200Z on 01 Dec 2005

IA. Analysis of Solar Active Regions and Activity from 30/2100Z to 01/2100Z: Solar activity decreased to low levels today. Region 826 (S02E22) continued to show explosive growth in both magnetic complexity and sunspot area. Magnetic analysis shows a strong east-west neutral line through the delta spot in the geometric center of the sunspot cluster. Region 826 produced multiple B and C-class flares during the period, the largest was a C6 x-ray flare occurring at 01/0837Z. Region 824 (S14W75) underwent little change since yesterday but did produce a C2 x-ray flare at 01/0238Z, which had an associated Type II radio sweep with an estimated shock velocity of 487 km/sec. Region 828 (S04E42) is a rapidly emerging DSO beta group that was numbered today.

IB. Solar Activity Forecast: Solar activity is expected to be at low to moderate levels. Region 826 has the potential to produce M-class flare activity.

IIA. Geophysical Activity Summary 30/2100Z to 01/2100Z: The geomagnetic field was at quiet to active levels. The elevated conditions are due to a recurrent high speed coronal hole stream. The solar wind speed has ranged between 650 and 750 km/sec throughout most of the period.

IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be at predominantly quiet to unsettled levels with isolated active conditions on 02 December due to a favorability positioned coronal hole. Conditions should decrease to quiet to unsettled levels on 03 and 04 December.

III. Event Probabilities 02 Dec-04 Dec

• Class M 50/50/50
• Class X 15/15/15
• Proton 05/05/05
• PCAF green

IV. Penticton 10.7 cm Flux

• Observed 01 Dec 098
• Predicted 02 Dec-04 Dec 100/105/105
• 90 Day Mean 01 Dec 085

V. Geomagnetic A Indices

• Observed Afr/Ap 30 Nov 009/010
• Estimated Afr/Ap 01 Dec 010/012
• Predicted Afr/Ap 02 Dec-04 Dec 012/015-010/012-005/008

VI. Geomagnetic Activity Probabilities 02 Dec-04 Dec

A. Middle Latitudes

• Active 25/20/15
• Minor storm 10/05/01
• Major-severe storm 05/01/01

B. High Latitudes

• Active 30/25/20
• Minor storm 15/10/05
• Major-severe storm 10/05/01