Joint USAF/NOAA Report of Solar and Geophysical Activity 18 Dec 2003
Prepared jointly by the U.S. Dept. of Commerce, NOAA, Space Environment Center and the U.S. Air Force.
Updated 2003 Dec 18 2210 UTC
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 352 Issued at 2200Z on 18 Dec 2003
IA. Analysis of Solar Active Regions and Activity from 17/2100Z
to 18/2100Z: Solar activity has been low. Several C-class flares
occurred over the period, including a C8.6/Sf at 18/0931Z from
Region 525 (N09E44). New Region 528 (N08E71) was numbered today,
and it produced several C-class flares including a C5.5 at 18/1209Z.
IB. Solar Activity Forecast: Solar activity is expected to be low
to moderate, with possible isolated major flares from Regions 525
and 528.
IIA. Geophysical Activity Summary 17/2100Z to 18/2100Z:
The geomagnetic field has been quiet to unsettled. The greater than
2 MeV electron flux at geosynchronous orbit remained at high levels
today.
IIB. Geophysical Activity Forecast: The geomagnetic field is
expected to increase from quiet to active levels over the next three
days. Isolated minor storming is possible due to the arrival of
high speed solar wind from a coronal hole moving into geoeffective
position beginning 19-20 December.
III. Event Probabilities 19 Dec-21 Dec
- Class M 20/20/20
- Class X 05/05/05
- Proton 01/01/01
- PCAF green
IV. Penticton 10.7 cm Flux
- Observed 18 Dec 123
- Predicted 19 Dec-21 Dec 130/135/135
- 90 Day Mean 18 Dec 137
V. Geomagnetic A Indices
- Observed Afr/Ap 17 Dec 004/010
- Estimated Afr/Ap 18 Dec 008/010
- Predicted Afr/Ap 19 Dec-21 Dec 015/015-015/020-010/015
VI. Geomagnetic Activity Probabilities 19 Dec-21 Dec
A. Middle Latitudes
- Active 45/45/35
- Minor storm 20/20/10
- Major-severe storm 05/05/01
B. High Latitudes
- Active 40/40/40
- Minor storm 25/30/20
- Major-severe storm 10/10/05
