Joint USAF/NOAA Report of Solar and Geophysical Activity 28 Jul 2008

Product: Report of Solar-Geophysical Activity
Issued: 2008 Jul 28 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 210 Issued at 2200Z on 28 Jul 2008

IA. Analysis of Solar Active Regions and Activity from 27/2100Z to 28/2100Z: Solar activity was very low. The visible disk is spotless. No flares occurred during the past 24 hours.

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

IIA. Geophysical Activity Summary 27/2100Z to 28/2100Z: The geomagnetic field was quiet to active. Active to unsettled conditions were observed from 27/2100Z to 28/0900Z, associated with a slight increase in solar wind velocity (up to 460 km/s) observed at ACE. Activity declined to quiet levels for the remainder of the period.

IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be quiet for the next three days (29-31 July).

III. Event Probabilities 29 Jul-31 Jul

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

IV. Penticton 10.7 cm Flux

• Observed 28 Jul 066
• Predicted 29 Jul-31 Jul 066/066/066
• 90 Day Mean 28 Jul 067

V. Geomagnetic A Indices

• Observed Afr/Ap 27 Jul 004/007
• Estimated Afr/Ap 28 Jul 005/008
• Predicted Afr/Ap 29 Jul-31 Jul 005/005-005/005-005/005

VI. Geomagnetic Activity Probabilities 29 Jul-31 Jul

A. Middle Latitudes

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

B. High Latitudes

• Active 15/15/15
• Minor storm 01/01/01
• Major-severe storm 01/01/01