Joint USAF/NOAA Report of Solar and Geophysical Activity 19 Sep 2006

Product: Report of Solar-Geophysical Activity
Issued: 2006 Sep 19 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 262 Issued at 2200Z on 19 Sep 2006

IA. Analysis of Solar Active Regions and Activity from 18/2100Z to 19/2100Z: Solar activity was very low. Region 910 (S09E37) produced occasional B-class flares. A weak Type II radio sweep was observed at 18/2356Z, which was associated with a faint CME from Region 910. The CME is not expected to be geoeffective.

IB. Solar Activity Forecast: Solar activity is expected to be very low. There is a slight chance for a C-class flare from Region 910.

IIA. Geophysical Activity Summary 18/2100Z to 19/2100Z: The geomagnetic field was quiet to active. The disturbed periods were in response to a high speed coronal hole stream. Solar wind speed was near 650 km/s, but gradually declined to under 500 km/s by the end of the period. The greater than 2MeV electron flux at geosynchronous orbit was at high levels again today.

IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be quiet to unsettled.

III. Event Probabilities 20 Sep-22 Sep

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

IV. Penticton 10.7 cm Flux

• Observed 19 Sep 073
• Predicted 20 Sep-22 Sep 075/075/075
• 90 Day Mean 19 Sep 077

V. Geomagnetic A Indices

• Observed Afr/Ap 18 Sep 016/024
• Estimated Afr/Ap 19 Sep 012/012
• Predicted Afr/Ap 20 Sep-22 Sep 008/008-005/008-005/005

VI. Geomagnetic Activity Probabilities 20 Sep-22 Sep

A. Middle Latitudes

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

B. High Latitudes

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