Viewing archive of Thursday, 7 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 07 2215 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 250 Issued at 2200Z on 07 Sep 2017IA. Analysis of Solar Active Regions and Activity from 06-2100Z to 07-2100Z Solar activity has been at high levels for the past 24 hours.
The largest solar event of the period was a X1 event observed at
07/1436Z from Region 2673 (S09W58). 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, two, and three (08 Sep, 09
Sep, 10 Sep).
IIA. Geophysical Activity Summary 06-2100Z to 07-2100Z
The geomagnetic
field has been at quiet to active levels for the past 24 hours. Solar
wind speed reached a peak of 666 km/s at 07/1156Z. Total IMF reached 16
nT at 07/0015Z. The maximum southward component of Bz reached -10 nT at
07/0600Z. Protons greater than 10 MeV at geosynchronous orbit reached a
peak level of 352 pfu at 07/0410Z. Electrons greater than 2 MeV at
geosynchronous orbit reached a peak level of 5443 pfu.
IIB. Geophysical Activity Forecast
The geomagnetic field is expected
to be at active to severe storm levels on days one and two (08 Sep, 09
Sep) and active to minor storm levels on day three (10 Sep). Protons are
expected to cross threshold on days one and two (08 Sep, 09 Sep) and are
expected to cross threshold on day three (10 Sep).
III. Event Probabilities 08 Sep to 10 Sep
| Class M | 75% | 75% | 75% |
| Class X | 50% | 50% | 50% |
| Proton | 99% | 99% | 95% |
| PCAF | red | ||
IV. Penticton 10.7 cm Flux
Observed 07 Sep 129 Predicted 08 Sep-10 Sep 125/125/120 90 Day Mean 07 Sep 080
V. Geomagnetic A Indices
Observed Afr/Ap 06 Sep 018/010 Estimated Afr/Ap 07 Sep 021/032 Predicted Afr/Ap 08 Sep-10 Sep 035/065-031/050-021/030
VI. Geomagnetic Activity Probabilities 08 Sep to 10 Sep
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 15% | 15% | 40% |
| Minor storm | 35% | 35% | 20% |
| Major-severe storm | 50% | 50% | 05% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 10% | 10% | 15% |
| Minor storm | 20% | 25% | 25% |
| Major-severe storm | 55% | 60% | 45% |
All times in UTC
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