Joint USAF/NOAA Report of Solar and Geophysical Activity 24 Oct 2007

Product: Report of Solar-Geophysical Activity
Issued: 2007 Oct 24 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 297 Issued at 2200Z on 24 Oct 2007

IA. Analysis of Solar Active Regions and Activity from 23/2100Z to 24/2100Z: Solar activity was at very low levels. The visible solar disk remained spotless.

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

IIA. Geophysical Activity Summary 23/2100Z to 24/2100Z: The geomagnetic field was at quiet levels. 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 at quiet to active levels due to a coronal hole high speed stream rotating into a geoeffective position on day one (25 October). Minor storm periods at middle latitudes and major storm periods at high latitudes are possible throughout the forecast period (25 – 27 October).

III. Event Probabilities 25 Oct-27 Oct

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

IV. Penticton 10.7 cm Flux

• Observed 24 Oct 068
• Predicted 25 Oct-27 Oct 067/067/067
• 90 Day Mean 24 Oct 068

V. Geomagnetic A Indices

• Observed Afr/Ap 23 Oct 006/007
• Estimated Afr/Ap 24 Oct 005/005
• Predicted Afr/Ap 25 Oct-27 Oct 015/020-020/025-012/012

VI. Geomagnetic Activity Probabilities 25 Oct-27 Oct

A. Middle Latitudes

• Active 30/35/25
• Minor storm 15/20/15
• Major-severe storm 05/10/05

B. High Latitudes

• Active 35/40/25
• Minor storm 25/30/20
• Major-severe storm 15/20/10