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

Product: Report of Solar-Geophysical Activity
Issued: 2008 Feb 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 052 Issued at 2200Z on 21 Feb 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 mostly quiet levels. From 21/1200 – 1500Z, an isolated unsettled period was observed. This increase in activity was due to sustained southward Bz. The greater than 2 MeV electron flux at geosynchronous orbit reached high levels again today.

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

III. Event Probabilities 22 Feb-24 Feb

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

IV. Penticton 10.7 cm Flux

• Observed 21 Feb 072
• Predicted 22 Feb-24 Feb 070/070/070
• 90 Day Mean 21 Feb 075

V. Geomagnetic A Indices

• Observed Afr/Ap 20 Feb 005/007
• Estimated Afr/Ap 21 Feb 005/005
• Predicted Afr/Ap 22 Feb-24 Feb 005/005-005/005-005/005

VI. Geomagnetic Activity Probabilities 22 Feb-24 Feb

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