Joint USAF/NOAA Report of Solar and Geophysical Activity 31 Jan 2007

Product: Report of Solar-Geophysical Activity
Issued: 2007 Jan 31 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 031 Issued at 2200Z on 31 Jan 2007

IA. Analysis of Solar Active Regions and Activity from 30/2100Z to 31/2100Z: Solar activity has been very low. Region 940 (S04E09) has produced only B-class activity during the past 24 hours.

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

IIA. Geophysical Activity Summary 30/2100Z to 31/2100Z: The geomagnetic field was unsettled to active. Solar wind speed remains elevated at approximately 600 km/s due to the coronal hole high speed stream. The greater then 2 MeV electron flux at geosynchronous orbit reached high levels again today.

IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be quiet to unsettled for the next three days (01 – 03 February). There is a chance for isolated active periods on 01 February due to the coronal hole high speed stream.

III. Event Probabilities 01 Feb-03 Feb

• Class M 05/05/05
• Class X 01/01/01
• Proton 01/01/01
• PCAF green

IV. Penticton 10.7 cm Flux

• Observed 31 Jan 089
• Predicted 01 Feb-03 Feb 090/090/090
• 90 Day Mean 31 Jan 081

V. Geomagnetic A Indices

• Observed Afr/Ap 30 Jan 017/021
• Estimated Afr/Ap 31 Jan 015/015
• Predicted Afr/Ap 01 Feb-03 Feb 010/010-005/005-005/005

VI. Geomagnetic Activity Probabilities 01 Feb-03 Feb

A. Middle Latitudes

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

B. High Latitudes

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