Joint USAF/NOAA Report of Solar and Geophysical Activity 13 Feb 2004
Prepared jointly by the U.S. Dept. of Commerce, NOAA, Space Environment Center and the U.S. Air Force.
Updated 2004 Feb 13 2210 UTC
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 044 Issued at 2200Z on 13 Feb 2004
IA. Analysis of Solar Active Regions and Activity from 12/2100Z
to 13/2100Z: Solar activity has been very low. X-ray flux remains
at background levels. Two new regions were numbered today: Region
557 (S11W32) and Region 558 (S15E36).
IB. Solar Activity Forecast: Solar activity is expected to be very
low. Region 554 may produce C-class flares.
IIA. Geophysical Activity Summary 12/2100Z to 13/2100Z:
The geomagnetic field has been predominantly active, with one period
of isolated minor storming. The geomagnetic field is still under
the influence of high speed solar wind stream from a geoeffective
coronal hole, although solar wind speeds have begun to subside. The
greater than 2 MeV electron flux at geosynchronous orbit reached
high levels today.
IIB. Geophysical Activity Forecast: The geomagnetic field is
expected to be unsettled to active on 14 February, with isolated
minor storming possible. Activity should decrease to quiet or
unsettled levels on 15 and 16 February as the coronal hole rotates
out of geoeffective position.
III. Event Probabilities 14 Feb-16 Feb
- Class M 10/10/10
- Class X 05/05/05
- Proton 01/01/01
- PCAF green
IV. Penticton 10.7 cm Flux
- Observed 13 Feb 108
- Predicted 14 Feb-16 Feb 110/110/110
- 90 Day Mean 13 Feb 120
V. Geomagnetic A Indices
- Observed Afr/Ap 12 Feb 016/028
- Estimated Afr/Ap 13 Feb 018/020
- Predicted Afr/Ap 14 Feb-16 Feb 015/020-012/020-010/015
VI. Geomagnetic Activity Probabilities 14 Feb-16 Feb
A. Middle Latitudes
- Active 30/30/25
- Minor storm 15/15/10
- Major-severe storm 05/01/01
B. High Latitudes
- Active 45/40/35
- Minor storm 30/25/25
- Major-severe storm 10/10/05
