Joint USAF/NOAA Report of Solar and Geophysical Activity 10 Sep 2003

SDF Number 253 Issued at 2200Z on 10 Sep 2003

IA. Analysis of Solar Active Regions and Activity from 09/2100Z
to 10/2100Z: Solar activity remained at very low levels today.
Region 456 (S09W19) produced several low level B-class flares today.
This region has shown rapid spot growth over the past 24 hours.
Magnetic analysis depicts a gamma structure in the trailing polarity
of the spot cluster. Region 457 (S11W06) remains a magnetically
simple complex with several small umbra visible in white light. No
new regions were numbered today.

IB. Solar Activity Forecast: Solar activity is expected to be at
very low to low levels. Region 456 is showing potential for C-class
flare production.

IIA. Geophysical Activity Summary 09/2100Z to 10/2100Z:
The geomagnetic field was at quiet to active levels. A favorably
positioned recurrent high speed coronal hole stream is responsible
for the elevated conditions.

IIB. Geophysical Activity Forecast: The geomagnetic field is
expected to be at predominantly quiet to active levels through day
one of the period. The return of quiet to unsettled conditions are
expected on days two and three.

III. Event Probabilities 11 Sep-13 Sep

• Class M 15/15/15
• Class X 01/01/01
• Proton 01/01/01
• PCAF green

IV. Penticton 10.7 cm Flux

• Observed 10 Sep 099
• Predicted 11 Sep-13 Sep 105/110/110
• 90 Day Mean 10 Sep 122

V. Geomagnetic A Indices

• Observed Afr/Ap 09 Sep 017/019
• Estimated Afr/Ap 10 Sep 020/020
• Predicted Afr/Ap 11 Sep-13 Sep 012/015-010/010-010/010

VI. Geomagnetic Activity Probabilities 11 Sep-13 Sep

A. Middle Latitudes

• Active 30/20/20
• Minor storm 10/05/05
• Major-severe storm 01/01/01

B. High Latitudes

• Active 35/25/25
• Minor storm 15/05/05
• Major-severe storm 05/01/01