Joint USAF/NOAA Report of Solar and Geophysical Activity 22 Dec 2006

Product: Report of Solar-Geophysical Activity
Issued: 2006 Dec 22 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 356 Issued at 2200Z on 22 Dec 2006

IA. Analysis of Solar Active Regions and Activity from 21/2100Z to 22/2100Z: Solar activity continues at very low levels. No activity of note was observed from old active Region 926, which is rotating onto the visible disk near S08.

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

IIA. Geophysical Activity Summary 21/2100Z to 22/2100Z: The geomagnetic field ranged from quiet to active. A high speed coronal hole stream is creating occasional active periods. Solar wind speed increased to near 750 km/s this period. The greater than 2 MeV electron flux at geosynchronous orbit was at high levels again this period.

IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be quiet to active on 23 December. Quiet to unsettled conditions are expected on 24 and 25 December.

III. Event Probabilities 23 Dec-25 Dec

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

IV. Penticton 10.7 cm Flux

• Observed 22 Dec 073
• Predicted 23 Dec-25 Dec 075/075/075
• 90 Day Mean 22 Dec 081

V. Geomagnetic A Indices

• Observed Afr/Ap 21 Dec 009/014
• Estimated Afr/Ap 22 Dec 012/015
• Predicted Afr/Ap 23 Dec-25 Dec 010/015-008/010-005/005

VI. Geomagnetic Activity Probabilities 23 Dec-25 Dec

A. Middle Latitudes

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

B. High Latitudes

• Active 40/30/20
• Minor storm 20/10/05
• Major-severe storm 05/01/01