Viewing archive of Saturday, 16 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 16 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 106 Issued at 2200Z on 16 Apr 2011IA. Analysis of Solar Active Regions and Activity from 15-2100Z to 16-2100Z Solar activity was at low levels. Occasional C-class
flares were observed during the period. Two C5 flares were observed
from Region 1190 (N14W40): a C5/Sf flare at 16/0057Z and a C5/Sf
flare at 16/1414Z. Additionally, Region 1185 (N14W93) produced a C3
flare at 16/1653Z Regions 1190 and 1193 continue to remain the most
significant regions on the disk. The CME mentioned in the forecast
yesterday is not expected to disturb the field during the forecast
period (17-19 April).
IB. Solar Activity Forecast
Solar activity is expected to be at
low levels, with C-class flares expected for the next three days
(17-19 April). There is also a chance for M-class flares during the
period.
IIA. Geophysical Activity Summary 15-2100Z to 16-2100Z
The geomagnetic field was at quiet levels. The greater than 2 MeV
electron flux at geosynchronous orbit reached high levels during the
period.
IIB. Geophysical Activity Forecast
The geomagnetic field is
expected to be at predominantly quiet levels for the next three days
(17-19 April).
III. Event Probabilities 17 Apr to 19 Apr
| Class M | 40% | 40% | 40% |
| Class X | 05% | 05% | 05% |
| Proton | 05% | 05% | 05% |
| PCAF | Green | ||
IV. Penticton 10.7 cm Flux
Observed 16 Apr 119 Predicted 17 Apr-19 Apr 123/125/128 90 Day Mean 16 Apr 103
V. Geomagnetic A Indices
Observed Afr/Ap 15 Apr 003/006 Estimated Afr/Ap 16 Apr 002/005 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 | 05% | 05% | 05% |
| Minor storm | 01% | 01% | 01% |
| Major-severe storm | 01% | 01% | 01% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 10% | 10% | 10% |
| Minor storm | 01% | 01% | 01% |
| Major-severe storm | 01% | 01% | 01% |
All times in UTC
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