Viewing archive of Friday, 8 September 2017
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 2017 Sep 08 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 251 Issued at 2200Z on 08 Sep 2017IA. Analysis of Solar Active Regions and Activity from 07-2100Z to 08-2100Z
Solar activity has been at high levels for the past 24 hours.
The largest solar event of the period was a M8 event observed at
08/0749Z from Region 2673 (S09W70). There are currently 5 numbered
sunspot regions on the disk.
IB. Solar Activity Forecast
Solar activity is expected to be moderate
with a chance for X-class flares on days one and two (09 Sep, 10 Sep)
and expected to be low with a chance for M-class flares and a slight
chance for an X-class flare on day three (11 Sep).
IIA. Geophysical Activity Summary 07-2100Z to 08-2100Z
The geomagnetic
field has been at active to severe storm levels for the past 24 hours.
Solar wind speed reached a peak of 1110 km/s at 08/0431Z. Total IMF
reached 34 nT at 07/2258Z. The maximum southward component of Bz reached
-32 nT at 07/2257Z. Protons greater than 10 MeV at geosynchronous orbit
reached a peak level of 844 pfu at 08/0035Z. Electrons greater than 2
MeV at geosynchronous orbit reached a peak level of 1941 pfu.
IIB. Geophysical Activity Forecast
The geomagnetic field is expected
to be at quiet to major storm levels on day one (09 Sep) and quiet to
unsettled levels on days two and three (10 Sep, 11 Sep). Protons are
expected to cross threshold on day one (09 Sep), are likely to cross
threshold on day two (10 Sep) and have a chance of crossing threshold on
day three (11 Sep).
III. Event Probabilities 09 Sep to 11 Sep
| Class M | 75% | 75% | 50% |
| Class X | 50% | 50% | 20% |
| Proton | 99% | 70% | 50% |
| PCAF | yellow | ||
IV. Penticton 10.7 cm Flux
Observed 08 Sep 117 Predicted 09 Sep-11 Sep 115/105/090 90 Day Mean 08 Sep 081
V. Geomagnetic A Indices
Observed Afr/Ap 07 Sep 023/042 Estimated Afr/Ap 08 Sep 053/098 Predicted Afr/Ap 09 Sep-11 Sep 022/030-007/010-007/008
VI. Geomagnetic Activity Probabilities 09 Sep to 11 Sep
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 30% | 20% | 15% |
| Minor storm | 40% | 05% | 05% |
| Major-severe storm | 25% | 01% | 01% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 30% | 15% | 15% |
| Minor storm | 40% | 20% | 20% |
| Major-severe storm | 25% | 20% | 20% |
All times in UTC
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