Joint USAF/NOAA Report of Solar and Geophysical Activity 19 Aug 2003
SDF Number 231 Issued at 2200Z on 19 Aug 2003
IA. Analysis of Solar Active Regions and Activity from 18/2100Z
to 19/2100Z: Solar activity was moderate. Region 431 produced two
M-class flares, an M2/1n at 19/0759 UTC and an M2/2f at 19/1006 UTC.
The second M-flare was associated with a CME observed in LASCO
images to be directed to the southwest. Region 436 (N08E42) produced
a C5/Sf flare at 19/1826 UTC. Other disk regions were quiet. New
Region 437 (S22W27) emerged on the disk.
IB. Solar Activity Forecast: Solar activity is expected to be low
to moderate. A small M-class flares is possible in Region 431 or
436.
IIA. Geophysical Activity Summary 18/2100Z to 19/2100Z:
The geomagnetic field ranged from major storm to quiet levels. The
CME-induced disturbance that occurred yesterday appears to have
ended. The field has been at unsettled to quiet levels since about
19/0600 UTC.
IIB. Geophysical Activity Forecast: The geomagnetic field is
expected to be quiet to unsettled for the next 48 hours. Active
conditions may start on 22 August in response to a recurrent
high-speed coronal hole stream.
III. Event Probabilities 20 Aug-22 Aug
- Class M 25/25/25
- Class X 01/01/01
- Proton 01/01/01
- PCAF green
IV. Penticton 10.7 cm Flux
- Observed 19 Aug 117
- Predicted 20 Aug-22 Aug 115/110/105
- 90 Day Mean 19 Aug 127
V. Geomagnetic A Indices
- Observed Afr/Ap 18 Aug 046/086
- Estimated Afr/Ap 19 Aug 015/020
- Predicted Afr/Ap 20 Aug-22 Aug 015/015-015/015-020/025
VI. Geomagnetic Activity Probabilities 20 Aug-22 Aug
A. Middle Latitudes
- Active 15/15/30
- Minor storm 05/05/10
- Major-severe storm 01/01/05
B. High Latitudes
- Active 20/20/50
- Minor storm 10/10/15
- Major-severe storm 01/01/05
