Joint USAF/NOAA Report of Solar and Geophysical Activity 04 Nov 2004

Prepared jointly by the U.S. Dept. of Commerce, NOAA,
Space Environment Center and the U.S. Air Force.

Updated 2004 Nov 04 2210 UTC

Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 309 Issued at 2200Z on 04 Nov 2004

IA. Analysis of Solar Active Regions and Activity from 03/2100Z
to 04/2100Z: Solar activity decreased to low levels today. The
largest flare of the period was a long duration C6/Sf that occurred
at 04/0905Z from Region 696 (N09E19). There was an associated
Tenflare (210 sfu’s) and a Type IV spectral radio sweep. A partial
halo CME was also seen in SOHO/LASCO imagery shortly following this
event which appears to have the potential of becoming geoeffective.
There was a doubling of the sunspot area coverage and a magnetic
delta structure is now visible in the trailing portion of the spot
cluster. Region 693 (S15W31) remains impressive in appearance,
although there were no recorded flares and some decay was observed
during the day. There remains a weak delta structure in the
trailing portion of the sunspot complex. Region 691 (N13W94)
produced B and C class flares as this region exited the solar west
limb. No new regions were numbered today.

IB. Solar Activity Forecast: Solar activity is expected to be at
moderate levels. Region 693 and 696 are both capable of producing
an isolated major flare activity.

IIA. Geophysical Activity Summary 03/2100Z to 04/2100Z:
The geomagnetic field was at mostly quiet to unsettled levels today.
There was one active period at high latitudes occurring between
03/2100 and 2400Z.

IIB. Geophysical Activity Forecast: The geomagnetic field is
expected to be predominantly quiet to unsettled on 05 November. On
06 November the field is expected to see minor to major storming
conditions due to the effects of the M5/Sn event that occurred
yesterday producing a full halo CME from Region 696. A partial halo
CME resulting from the long duration C6/Sf flare that occurred at
04/0905Z is expected to produce minor storming conditions late on
the sixth, or early on 7 November.

III. Event Probabilities 05 Nov-07 Nov

• Class M 60/60/60
• Class X 20/20/20
• Proton 20/20/20
• PCAF yellow

IV. Penticton 10.7 cm Flux

• Observed 04 Nov 136
• Predicted 05 Nov-07 Nov 135/140/140
• 90 Day Mean 04 Nov 109

V. Geomagnetic A Indices

• Observed Afr/Ap 03 Nov 007/010
• Estimated Afr/Ap 04 Nov 008/010
• Predicted Afr/Ap 05 Nov-07 Nov 012/015-025/030-020/025

VI. Geomagnetic Activity Probabilities 05 Nov-07 Nov

A. Middle Latitudes

• Active 25/40/40
• Minor storm 15/35/25
• Major-severe storm 05/20/15

B. High Latitudes

• Active 30/30/35
• Minor storm 15/45/40
• Major-severe storm 05/20/15