Joint USAF/NOAA Report of Solar and Geophysical Activity 21 Jan 2008

Product: Report of Solar-Geophysical Activity
Issued: 2008 Jan 21 2200 UTC
Prepared jointly by the U.S. Dept. of Commerce, NOAA,
Space Weather Prediction Center and the U.S. Air Force.

Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 021 Issued at 2200Z on 21 Jan 2008

IA. Analysis of Solar Active Regions and Activity from 20/2100Z to 21/2100Z: Solar activity was at very low levels. The visible solar disk remained spotless.

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

IIA. Geophysical Activity Summary 20/2100Z to 21/2100Z: The geomagnetic field was at quiet levels. Solar wind speed measurements from the ACE spacecraft have been declining. At the end of the summary period wind speed was below 550 km/s. The greater than 2 MeV electron flux at geosynchronous orbit was at high levels again today.

IIB. Geophysical Activity Forecast: The geomagnetic field is expected to remain at quiet levels throughout the forecast period (22 – 24 January).

III. Event Probabilities 22 Jan-24 Jan

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

IV. Penticton 10.7 cm Flux

• Observed 21 Jan 072
• Predicted 22 Jan-24 Jan 070/070/070
• 90 Day Mean 21 Jan 074

V. Geomagnetic A Indices

• Observed Afr/Ap 20 Jan 004/006
• Estimated Afr/Ap 21 Jan 003/005
• Predicted Afr/Ap 22 Jan-24 Jan 005/005-005/005-005/005

VI. Geomagnetic Activity Probabilities 22 Jan-24 Jan

A. Middle Latitudes

• Active 05/05/05
• Minor storm 01/01/01
• Major-severe storm 01/01/01

B. High Latitudes

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