Viewing archive of Friday, 28 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 28 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 240 Issued at 2200Z on 28 Aug 2015IA. Analysis of Solar Active Regions and Activity from 27-2100Z to 28-2100Z Solar activity has been at moderate levels for the past 24
hours. The largest solar event of the period was a M2 event observed at
28/1316Z from Region 2403 (S15W69). There are currently 2 numbered
sunspot regions on the disk.
IB. Solar Activity Forecast
Solar activity is likely to be moderate
with a slight chance for an X-class flare on days one and two (29 Aug,
30 Aug) and expected to be low with a chance for M-class flares on day
three (31 Aug).
IIA. Geophysical Activity Summary 27-2100Z to 28-2100Z
The geomagnetic
field has been at unsettled to major storm levels for the past 24 hours.
Solar wind speed, as measured by the ACE spacecraft, reached a peak
speed of 440 km/s at 28/1841Z. Total IMF reached 17 nT at 28/1801Z. The
maximum southward component of Bz reached -16 nT at 28/1708Z. Electrons
greater than 2 MeV at geosynchronous orbit reached a peak level of 256
pfu.
IIB. Geophysical Activity Forecast
The geomagnetic field is expected
to be at unsettled to minor storm levels on day one (29 Aug), quiet to
active levels on day two (30 Aug) and quiet to unsettled levels on day
three (31 Aug). Protons greater than 10 Mev have a slight chance of
crossing threshold on days one and two (29 Aug, 30 Aug).
III. Event Probabilities 29 Aug to 31 Aug
| Class M | 60% | 60% | 50% |
| Class X | 10% | 10% | 05% |
| Proton | 10% | 10% | 05% |
| PCAF | green | ||
IV. Penticton 10.7 cm Flux
Observed 28 Aug 109 Predicted 29 Aug-31 Aug 110/105/100 90 Day Mean 28 Aug 112
V. Geomagnetic A Indices
Observed Afr/Ap 27 Aug 026/051 Estimated Afr/Ap 28 Aug 033/048 Predicted Afr/Ap 29 Aug-31 Aug 019/025-010/012-009/008
VI. Geomagnetic Activity Probabilities 29 Aug to 31 Aug
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 40% | 30% | 15% |
| Minor storm | 25% | 10% | 05% |
| Major-severe storm | 05% | 01% | 01% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 10% | 15% | 15% |
| Minor storm | 25% | 30% | 25% |
| Major-severe storm | 60% | 40% | 25% |
All times in UTC
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