Viewing archive of Tuesday, 26 April 2011
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 2011 Apr 26 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 116 Issued at 2200Z on 26 Apr 2011IA. Analysis of Solar Active Regions and Activity from 25-2100Z to 26-2100Z
Solar activity has been at been at very low levels for
the past 24 hours. Region 1195 (S17W25) has started to decay , with
a decrease in both sunspot number and areal coverage. Two new
Regions were numbered today, Region 1199 (N21W23) and Region 1200
(S17E42). Region 1199 emerged quickly on the disk and is already
classified as a C-type group.
IB. Solar Activity Forecast
Solar activity is expected to be at
very low to low levels for the next three days (27-29 April).
IIA. Geophysical Activity Summary 25-2100Z to 26-2100Z
The geomagnetic field has been at quiet levels for the past 24 hours.
Solar wind speed, as measured by the ACE spacecraft, has continued
to decrease from around 450 - 400 km/s.
IIB. Geophysical Activity Forecast
The geomagnetic field is
expected to be at mostly quiet levels for the next three days (27-29
April).
III. Event Probabilities 27 Apr to 29 Apr
| Class M | 10% | 05% | 05% |
| Class X | 01% | 01% | 01% |
| Proton | 01% | 01% | 01% |
| PCAF | green | ||
IV. Penticton 10.7 cm Flux
Observed 26 Apr 109 Predicted 27 Apr-29 Apr 105/105/105 90 Day Mean 26 Apr 106
V. Geomagnetic A Indices
Observed Afr/Ap 25 Apr 002/006 Estimated Afr/Ap 26 Apr 003/003 Predicted Afr/Ap 27 Apr-29 Apr 005/005-005/005-005/005
VI. Geomagnetic Activity Probabilities 27 Apr to 29 Apr
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 10% | 05% | 10% |
| Minor storm | 01% | 01% | 01% |
| Major-severe storm | 01% | 01% | 01% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 15% | 05% | 10% |
| Minor storm | 01% | 01% | 01% |
| Major-severe storm | 01% | 01% | 01% |
All times in UTC
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