Joint USAF/NOAA Report of Solar and Geophysical Activity 25 Oct 2003
Prepared jointly by the U.S. Dept. of Commerce, NOAA,
Space Environment Center and the U.S. Air Force.
Updated 2003 Oct 25 2200 UTC
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 298 Issued at 2200Z on 25 Oct 2003
IA. Analysis of Solar Active Regions and Activity from 24/2100Z
to 25/2100Z: Solar activity has been moderate. Region 484 (N04W28)
produced three M-class flares, the strongest being a M1.7/Sf at
25/0553 UTC with an associated Type II radio sweep. At 24/0446 UTC,
Region 486 produced an M1.2/2n with an associated CME with a speed
of approximately 585 km/s. This CME did not appear to be
earth-directed. Both regions maintained their magnetic complexity
and grew slightly in size. Region 486 is now observed at 2200 mils.
A 10-degree filament erupted at S24W41 sometime between 24/2342 and
25/1417 UTC. New Region 487 at N13E72 was numbered today.
IB. Solar Activity Forecast: Solar activity is expected to be
moderate to high. Regions 484 and 486 are expected to produce
M-class and isolated X-class flares.
IIA. Geophysical Activity Summary 24/2100Z to 25/2100Z:
The geomagnetic field has been quiet to active. Residual effects
from yesterday’s transient arrival continue to cause occasional
active conditions. Solar wind speed has decreased steadily to about
500 km/s, and Bz continues to maintain a consistent northward
orientation.
IIB. Geophysical Activity Forecast: The geomagnetic field is
expected to be quiet to active throughout the period, with isolated
minor storm conditions possible on day one.
III. Event Probabilities 26 Oct-28 Oct
- Class M 85/85/85
- Class X 40/40/40
- Proton 10/15/20
- PCAF yellow
IV. Penticton 10.7 cm Flux
- Observed 25 Oct 222
- Predicted 26 Oct-28 Oct 210/210/200
- 90 Day Mean 25 Oct 119
V. Geomagnetic A Indices
- Observed Afr/Ap 24 Oct 028/034
- Estimated Afr/Ap 25 Oct 015/020
- Predicted Afr/Ap 26 Oct-28 Oct 020/025-015/020-010/015
VI. Geomagnetic Activity Probabilities 26 Oct-28 Oct
A. Middle Latitudes
- Active 30/30/30
- Minor storm 30/30/30
- Major-severe storm 15/10/05
B. High Latitudes
- Active 30/30/30
- Minor storm 40/40/40
- Major-severe storm 25/20/20