Joint USAF/NOAA Report of Solar and Geophysical Activity 17 Dec 2002
SDF Number 351 Issued at 2200Z on 17 Dec 2002
IA. Analysis of Solar Active Regions and Activity from 16/2100Z
to 17/2100Z: Solar activity was moderate. Region 226 (S18W01)
produced an M1.9/1n flare at 16/2255 UTC. This region has continued
to grow in size and complexity, and appears to contain a magnetic
delta configuration in its intermediate spots. Shortly following
the aforementioned flare, Region 227 (N07W20) produced a subfaint
optical flare that corresponded with an impulsive M1.3 x-ray
enhancement at 16/2336 UTC. Other flare activity included several
C-class events from the regions noted above as well as Region 225
(N17E11). New Region 230 (S08E59) was numbered today.
IB. Solar Activity Forecast: Solar activity is expected to be low
to moderate for the next three days. A slight chance for an
isolated major flare event is possible, particularly from Region
226.
IIA. Geophysical Activity Summary 16/2100Z to 17/2100Z:
The geomagnetic field was quiet, with one isolated unsettled period
at higher latitudes during 17/1500-1800 UTC.
IIB. Geophysical Activity Forecast: The geomagnetic field is
expected to be quiet to active during day one of the forecast
period, and predominantly active with isolated storming intervals
possible during the remainder of the period, due to the expected
onset of recurrent coronal hole effects.
III. Event Probabilities 18 Dec-20 Dec
- Class M 50/50/50
- Class X 05/05/05
- Proton 05/05/05
- PCAF green
IV. Penticton 10.7 cm Flux
- Observed 17 Dec 213
- Predicted 18 Dec-20 Dec 205/205/195
- 90 Day Mean 17 Dec 165
V. Geomagnetic A Indices
- Observed Afr/Ap 16 Dec 003/008
- Estimated Afr/Ap 17 Dec 004/010
- Predicted Afr/Ap 18 Dec-20 Dec 015/015-020/035-018/025
VI. Geomagnetic Activity Probabilities 18 Dec-20 Dec
A. Middle Latitudes
- Active 25/35/30
- Minor storm 05/10/10
- Major-severe storm 01/05/05
B. High Latitudes
- Active 35/45/40
- Minor storm 10/15/15
- Major-severe storm 01/10/05
