Viewing archive of Saturday, 16 April 2005
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 2005 Apr 16 2210 UTC# Prepared jointly by the U.S. Dept. of Commerce, NOAA, #Space Environment Center and the U.S. Air Force. #
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 106 Issued at 2200Z on 16 Apr 2005IA. Analysis of Solar Active Regions and Activity from 15-2100Z to 16-2100Z Solar activity has been very low. Current active
regions on the solar disk remain steady, with no new regions
numbered today.
IB. Solar Activity Forecast
Solar activity is expected to remain
very low.
IIA. Geophysical Activity Summary 15-2100Z to 16-2100Z
The geomagnetic field has been at quiet to unsettled levels. The
greater than 2 MeV electron flux at geosynchronous orbit reached
high levels today.
IIB. Geophysical Activity Forecast
The geomagnetic field is
expected to remain at quiet to unsettled levels through 19 Apr.
III. Event Probabilities 17 Apr to 19 Apr
| Class M | 05% | 05% | 05% |
| Class X | 01% | 01% | 01% |
| Proton | 01% | 01% | 01% |
| PCAF | green | ||
IV. Penticton 10.7 cm Flux
Observed 16 Apr 083 Predicted 17 Apr-19 Apr 085/085/085 90 Day Mean 16 Apr 093
V. Geomagnetic A Indices
Observed Afr/Ap 15 Apr 007/013 Estimated Afr/Ap 16 Apr 005/008 Predicted Afr/Ap 17 Apr-19 Apr 005/005-005/005-005/005
VI. Geomagnetic Activity Probabilities 17 Apr to 19 Apr
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 15% | 15% | 15% |
| Minor storm | 01% | 01% | 01% |
| Major-severe storm | 01% | 01% | 01% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 20% | 20% | 20% |
| Minor storm | 05% | 05% | 05% |
| Major-severe storm | 02% | 02% | 02% |
All times in UTC
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