Joint USAF/NOAA Report of Solar and Geophysical Activity 31 Jan 2004
Prepared jointly by the U.S. Dept. of Commerce, NOAA,
Space Environment Center and the U.S. Air Force.
Updated 2004 Jan 31 2210 UTC
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 031 Issued at 2200Z on 31 Jan 2004
IA. Analysis of Solar Active Regions and Activity from 30/2100Z
to 31/2100Z: Solar activity was low. New Region 549 (N13E70)
continued to produce B and C-class flares. The largest flare was a
C4 at 31/0622 UTC. This region is still close to the limb but
appears to be a D-type sunspot group of moderate size. New Region
498 (N06E30) was also numbered today.
IB. Solar Activity Forecast: Solar activity is expected to be low.
Additional small flares are expected in Region 549. There is a
chance of a small M-class flare in this region as well.
IIA. Geophysical Activity Summary 30/2100Z to 31/2100Z:
The geomagnetic field ranged from quiet to minor storm levels under
the influence of a coronal hole high-speed stream.
IIB. Geophysical Activity Forecast: The geomagnetic field is
expected to be mostly unsettled to active with the possibility of
isolated minor storm periods as the coronal hole induced disturbance
continues.
III. Event Probabilities 01 Feb-03 Feb
- Class M 25/25/25
- Class X 01/01/01
- Proton 01/01/01
- PCAF green
IV. Penticton 10.7 cm Flux
- Observed 31 Jan 094
- Predicted 01 Feb-03 Feb 100/105/105
- 90 Day Mean 31 Jan 121
V. Geomagnetic A Indices
- Observed Afr/Ap 30 Jan 019/017
- Estimated Afr/Ap 31 Jan 015/015
- Predicted Afr/Ap 01 Feb-03 Feb 015/020-015/020-015/025
VI. Geomagnetic Activity Probabilities 01 Feb-03 Feb
A. Middle Latitudes
- Active 30/30/30
- Minor storm 10/10/10
- Major-severe storm 05/05/05
B. High Latitudes
- Active 50/50/50
- Minor storm 15/15/15
- Major-severe storm 10/10/10
