Joint USAF/NOAA Report of Solar and Geophysical Activity 22 Dec 2004

Prepared jointly by the U.S. Dept. of Commerce, NOAA,
Space Environment Center and the U.S. Air Force.
Updated 2004 Dec 22 2350 UTC

Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 357 Issued at 2200Z on 22 Dec 2004

IA. Analysis of Solar Active Regions and Activity from 21/2100Z
to 22/2100Z: Solar activity was low. Region 713 (S10E07) produced a
C2/Sf event at 22/2025 UTC. This region has went relatively
unchanged and retains a beta-gamma magnetic configuration. A new
region was numbered today as Region 714 (S04W01).

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

IIA. Geophysical Activity Summary 21/2100Z to 22/2100Z:
The geomagnetic field was quiet to minor storm conditions. The ACE
solar wind data suggest the possible influence of a high speed solar
wind stream. In the past 24 hours the solar wind velocity has
steadily increased from around 400 km/s to above 550 km/s with
southward fluctuating Bz, and low density.

IIB. Geophysical Activity Forecast: The geomagnetic field is
expected to be quiet to unsettled with isolated periods of active
conditions.

III. Event Probabilities 23 Dec-25 Dec

• Class M 25/25/25
• Class X 01/01/01
• Proton 01/01/01
• PCAF Green

IV. Penticton 10.7 cm Flux

• Observed 22 Dec 099
• Predicted 23 Dec-25 Dec 105/105/105
• 90 Day Mean 22 Dec 104

V. Geomagnetic A Indices

• Observed Afr/Ap 21 Dec 006/012
• Estimated Afr/Ap 22 Dec 015/020
• Predicted Afr/Ap 23 Dec-25 Dec 012/015-010/010-012/015

VI. Geomagnetic Activity Probabilities 23 Dec-25 Dec

A. Middle Latitudes

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

B. High Latitudes

• Active 30/25/30
• Minor storm 15/15/15
• Major-severe storm 05/01/05