Viewing archive of Wednesday, 20 October 2004
Solar activity report
Any mentioned solar flare in this report has a scaling factor applied by the Space Weather Prediction Center (SWPC). Because of the SWPC scaling factor, solar flares are reported as 42% smaller than for the science quality data. The scaling factor has been removed from our archived solar flare data to reflect the true physical units.
Report of Solar-Geophysical Activity 2004 Oct 20 2200 UTC
Prepared by the NOAA © SWPC and processed by SpaceWeatherLive.comJoint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 294 Issued at 2200Z on 20 Oct 2004
IA. Analysis of Solar Active Regions and Activity from 19-2100Z to 20-2100Z
Solar activity increased to moderate levels. Region
687 (N10E65) produced the largest flare of the period, an M2 x-ray
flare that occurred at 20/1051Z. A CME was observed in LASCO
imagery which does not appear to be Earth directed. This region
remains too close to the eastern limb to fully discern magnetic
complexity, although it does appear to contain a compact cluster of
sunspots exhibiting both polarities. Region 682 (S13W33) produced
multiple low level flares today, the largest was a C4/Sf which
occurred at 20/0213Z. This region underwent moderate growth today.
A beta-gamma magnetic structure is now evident and the sunspot area
showed a modest increase during the period. Region 688 (S08W48)
showed moderate growth over the period and was numbered today.
IB. Solar Activity Forecast
Solar activity is expected to be at
low to moderate levels. Region 682 and 687 both have a fair
potential for the production of isolated M-class flare activity.
IIA. Geophysical Activity Summary 19-2100Z to 20-2100Z
The geomagnetic field was at quiet to active levels. Active levels
occurred in response to the sustained southward movement of the Bz
component of the interplanetary magnetic field.
IIB. Geophysical Activity Forecast
The geomagnetic field is
expected to be at quiet to unsettled levels throughout the period.
III. Event Probabilities 21 Oct to 23 Oct
Class M | 50% | 50% | 50% |
Class X | 01% | 01% | 01% |
Proton | 01% | 01% | 01% |
PCAF | Green
|
IV. Penticton 10.7 cm Flux
Observed 20 Oct 111
Predicted 21 Oct-23 Oct 115/120/125
90 Day Mean 20 Oct 105
V. Geomagnetic A Indices
Observed Afr/Ap 19 Oct 003/004
Estimated Afr/Ap 20 Oct 006/012
Predicted Afr/Ap 21 Oct-23 Oct 005/008-005/005-005/005
VI. Geomagnetic Activity Probabilities 21 Oct to 23 Oct
A. Middle Latitudes |
Active | 15% | 15% | 15% |
Minor storm | 01% | 01% | 01% |
Major-severe storm | 01% | 01% | 01% |
B. High Latitudes |
Active | 20% | 15% | 15% |
Minor storm | 05% | 05% | 05% |
Major-severe storm | 01% | 01% | 01% |
All times in UTC
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