Joint USAF/NOAA Report of Solar and Geophysical Activity 20 Nov 2005

Product: Report of Solar-Geophysical Activity
Issued: 2005 Nov 20 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 324 Issued at 2200Z on 20 Nov 2005

IA. Analysis of Solar Active Regions and Activity from 19/2100Z to 20/2100Z: Solar activity was low. Region 822 (S08W25) produced two C-class flares. A C2.5 flare occurred at 20/0736Z, and a C1.5 flare occurred at 20/1520Z. This region continues to slowly decay. New Region 824 (S13E68) rotated onto the visible disk today.

IB. Solar Activity Forecast: Solar activity is expected to be low to moderate. Region 822 is capable of producing an M-class flare.

IIA. Geophysical Activity Summary 19/2100Z to 20/2100Z: The geomagnetic field was predominantly quiet, with periods of active conditions occurring between 19/1500Z and 19/2100Z.

IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be at quiet to unsettled levels, with isolated active periods possible on 21 November due to a solar sector boundary crossing.

III. Event Probabilities 21 Nov-23 Nov

• Class M 40/40/40
• Class X 05/05/05
• Proton 05/05/05
• PCAF green

IV. Penticton 10.7 cm Flux

• Observed 20 Nov 096
• Predicted 21 Nov-23 Nov 095/095/095
• 90 Day Mean 20 Nov 085

V. Geomagnetic A Indices

• Observed Afr/Ap 19 Nov 006/010
• Estimated Afr/Ap 20 Nov 007/008
• Predicted Afr/Ap 21 Nov-23 Nov 012/015-008/008-005/005

VI. Geomagnetic Activity Probabilities 21 Nov-23 Nov

A. Middle Latitudes

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

B. High Latitudes

• Active 35/25/25
• Minor storm 20/10/05
• Major-severe storm 10/05/01