Viewing archive of Friday, 16 April 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 Apr 16 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 107 Issued at 2200Z on 16 Apr 2004IA. Analysis of Solar Active Regions and Activity from 15-2100Z to 16-2100Z Solar activity was at very low levels. The largest
flare of the period was a B8 from newly numbered Region 595(S09E68).
Region 591(S16W52) continues to show signs of decay but still has
some weak polarity mixing.
IB. Solar Activity Forecast
Solar activity is expected to be very
low to low. Region 591 and 595 have the potential for C-class
activity.
IIA. Geophysical Activity Summary 15-2100Z to 16-2100Z
The geomagnetic field was at quiet to active levels. Two periods of
active conditions were observed due to elevated wind speed and a
weak coronal hole influence.
IIB. Geophysical Activity Forecast
The geomagnetic field is
expected to be at quiet to unsettled levels with a chance of
isolated active conditions due to elevated solar wind speeds.
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 097 Predicted 17 Apr-19 Apr 100/100/100 90 Day Mean 16 Apr 108
V. Geomagnetic A Indices
Observed Afr/Ap 15 Apr 003/006 Estimated Afr/Ap 16 Apr 010/012 Predicted Afr/Ap 17 Apr-19 Apr 008/012-006/010-003/008
VI. Geomagnetic Activity Probabilities 17 Apr to 19 Apr
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 25% | 20% | 10% |
| Minor storm | 05% | 05% | 05% |
| Major-severe storm | 01% | 01% | 01% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 35% | 25% | 15% |
| Minor storm | 10% | 10% | 05% |
| Major-severe storm | 01% | 01% | 01% |
All times in UTC
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