Joint USAF/NOAA Report of Solar and Geophysical Activity 18 Jul 2007

Product: Report of Solar-Geophysical Activity
Issued: 2007 Jul 18 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 199 Issued at 2200Z on 18 Jul 2007

IA. Analysis of Solar Active Regions and Activity from 17/2100Z to 18/2100Z: Solar activity was very low. No significant activity has been observed during the past 24 hours.

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

IIA. Geophysical Activity Summary 17/2100Z to 18/2100Z: The geomagnetic field was quiet. 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 be quiet to unsettled with a chance for active periods on 19 July as a recurrent coronal hole moves into a geoeffective position. Expect unsettled to active conditions with possible isolated periods of minor storming on 20 – 21 July due to the ensuing coronal hole high speed stream.

III. Event Probabilities 19 Jul-21 Jul

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

IV. Penticton 10.7 cm Flux

• Observed 18 Jul 070
• Predicted 19 Jul-21 Jul 070/070/070
• 90 Day Mean 18 Jul 075

V. Geomagnetic A Indices

• Observed Afr/Ap 17 Jul 002/005
• Estimated Afr/Ap 18 Jul 002/005
• Predicted Afr/Ap 19 Jul-21 Jul 008/010-012/015-008/015

VI. Geomagnetic Activity Probabilities 19 Jul-21 Jul

A. Middle Latitudes

• Active 15/20/15
• Minor storm 05/10/05
• Major-severe storm 01/05/01

B. High Latitudes

• Active 20/25/25
• Minor storm 10/15/15
• Major-severe storm 05/05/05