Viewing archive of Friday, 21 August 2015
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 2015 Aug 21 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 233 Issued at 2200Z on 21 Aug 2015IA. Analysis of Solar Active Regions and Activity from 20-2100Z to 21-2100Z Solar activity has been at moderate levels for the past 24
hours. The largest solar event of the period was a M1 event observed at
21/0948Z from Region 2403 (S14E23). There are currently 3 numbered
sunspot regions on the disk.
IB. Solar Activity Forecast
Solar activity is expected to be low with
a chance for M-class flares and a slight chance for an X-class flare on
days one, two, and three (22 Aug, 23 Aug, 24 Aug).
IIA. Geophysical Activity Summary 20-2100Z to 21-2100Z
The geomagnetic
field has been at quiet to unsettled levels for the past 24 hours. Solar
wind speed, as measured by the ACE spacecraft, reached a peak speed of
558 km/s at 21/0106Z. Total IMF reached 6 nT at 20/2151Z. The maximum
southward component of Bz reached -5 nT at 20/2118Z. Electrons greater
than 2 MeV at geosynchronous orbit reached a peak level of 9116 pfu.
IIB. Geophysical Activity Forecast
The geomagnetic field is expected
to be at quiet to unsettled levels on day one (22 Aug), unsettled to
minor storm levels on day two (23 Aug) and quiet to active levels on day
three (24 Aug).
III. Event Probabilities 22 Aug to 24 Aug
| Class M | 35% | 35% | 35% |
| Class X | 10% | 10% | 10% |
| Proton | 01% | 01% | 01% |
| PCAF | green | ||
IV. Penticton 10.7 cm Flux
Observed 21 Aug 110 Predicted 22 Aug-24 Aug 110/110/115 90 Day Mean 21 Aug 110
V. Geomagnetic A Indices
Observed Afr/Ap 20 Aug 011/014 Estimated Afr/Ap 21 Aug 006/008 Predicted Afr/Ap 22 Aug-24 Aug 007/008-021/028-011/012
VI. Geomagnetic Activity Probabilities 22 Aug to 24 Aug
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 10% | 45% | 30% |
| Minor storm | 05% | 25% | 05% |
| Major-severe storm | 01% | 05% | 01% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 15% | 05% | 15% |
| Minor storm | 15% | 25% | 30% |
| Major-severe storm | 15% | 70% | 40% |
All times in UTC
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