Viewing archive of Friday, 26 April 2002
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 2002 Apr 26 2200 UTC
Prepared by the NOAA © SWPC and processed by SpaceWeatherLive.comJoint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 116 Issued at 2200Z on 26 Apr 2002
IA. Analysis of Solar Active Regions and Activity from 25-2100Z to 26-2100Z
Solar activity was low with very isolated low C-class
activity observed. Region 9912 (N11W78) continues to slowly decay as
it approaches the west limb. Regions 9914 (N04W25), 9915 (N11W12),
and 9919 (N12E33), exhibited minor growth. The remaining regions on
the visible disk were stable or in decay. A significant segment of
the large E-W filament centered near S32W12 disappeared late in the
period. It is too early to confirm if a CME accompanied this
filament eruption.
IB. Solar Activity Forecast
Solar activity is expected to continue
at low levels. Isolated low c-class flares are expected.
IIA. Geophysical Activity Summary 25-2100Z to 26-2100Z
The geomagnetic field was quiet. The greater than 10 MeV proton event
that began on 21/0225Z, and peaked on 21/2320Z at 2520 pfu, ended
today at 26/0715Z. The 10 MeV proton flux remains elevated at near 5
pfu, but continues to slowly decline.
IIB. Geophysical Activity Forecast
The geomagnetic field is
expected to become unsettled with isolated active periods. A
recurrent coronal hole is moving into a geoeffectively favorable
position; expect disturbed conditions to develop this period.
III. Event Probabilities 27 Apr to 29 Apr
Class M | 25% | 25% | 25% |
Class X | 05% | 05% | 05% |
Proton | 01% | 01% | 01% |
PCAF | in progress
|
IV. Penticton 10.7 cm Flux
Observed 26 Apr 163
Predicted 27 Apr-29 Apr 165/165/170
90 Day Mean 26 Apr 196
V. Geomagnetic A Indices
Observed Afr/Ap 25 Apr 002/005
Estimated Afr/Ap 26 Apr 005/007
Predicted Afr/Ap 27 Apr-29 Apr 012/015-012/012-010/010
VI. Geomagnetic Activity Probabilities 27 Apr to 29 Apr
A. Middle Latitudes |
Active | 35% | 35% | 30% |
Minor storm | 15% | 15% | 10% |
Major-severe storm | 05% | 05% | 01% |
B. High Latitudes |
Active | 40% | 40% | 35% |
Minor storm | 20% | 20% | 15% |
Major-severe storm | 05% | 05% | 01% |
All times in UTC
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