Joint USAF/NOAA Report of Solar and Geophysical Activity 20 Jul 2007

Product: Report of Solar-Geophysical Activity
Issued: 2007 Jul 20 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 201 Issued at 2200Z on 20 Jul 2007

IA. Analysis of Solar Active Regions and Activity from 19/2100Z to 20/2100Z: Solar activity has been very low. Region 963 has rotated off of the visible disk.

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

IIA. Geophysical Activity Summary 19/2100Z to 20/2100Z: The geomagnetic field ranged from unsettled to active conditions.

IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be unsettled for 21 July due to a recurrent coronal hole. There is the possibility of isolated active periods. Conditions are expected to return to quiet for 22 – 23 July.

III. Event Probabilities 21 Jul-23 Jul

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

IV. Penticton 10.7 cm Flux

• Observed 20 Jul 067
• Predicted 21 Jul-23 Jul 068/068/068
• 90 Day Mean 20 Jul 074

V. Geomagnetic A Indices

• Observed Afr/Ap 19 Jul 003/003
• Estimated Afr/Ap 20 Jul 012/015
• Predicted Afr/Ap 21 Jul-23 Jul 010/015-005/010-005/005

VI. Geomagnetic Activity Probabilities 21 Jul-23 Jul

A. Middle Latitudes

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

B. High Latitudes

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