Viewing archive of Monday, 4 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 04 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 247 Issued at 2200Z on 04 Sep 2017IA. Analysis of Solar Active Regions and Activity from 03-2100Z to 04-2100Z
Solar activity has been at high levels for the past 24 hours.
The largest solar event of the period was a M5 event observed at
04/2033Z. 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 (05 Sep, 06
Sep, 07 Sep).
IIA. Geophysical Activity Summary 03-2100Z to 04-2100Z
The geomagnetic
field has been at quiet to active levels for the past 24 hours. Solar
wind speed reached a peak of 524 km/s at 04/2007Z. Total IMF reached 9
nT at 04/2019Z. The maximum southward component of Bz reached -6 nT at
04/1649Z. Electrons greater than 2 MeV at geosynchronous orbit reached a
peak level of 15826 pfu.
IIB. Geophysical Activity Forecast
The geomagnetic field is expected
to be at quiet to unsettled levels on day one (05 Sep) and quiet levels
on days two and three (06 Sep, 07 Sep). Protons have a slight chance of
crossing threshold on days one, two, and three (05 Sep, 06 Sep, 07 Sep).
III. Event Probabilities 05 Sep to 07 Sep
| Class M | 71% | 71% | 71% |
| Class X | 25% | 25% | 25% |
| Proton | 10% | 10% | 10% |
| PCAF | green | ||
IV. Penticton 10.7 cm Flux
Observed 04 Sep 183 Predicted 05 Sep-07 Sep 140/140/130 90 Day Mean 04 Sep 079
V. Geomagnetic A Indices
Observed Afr/Ap 03 Sep 010/008 Estimated Afr/Ap 04 Sep 010/013 Predicted Afr/Ap 05 Sep-07 Sep 009/010-005/005-005/005
VI. Geomagnetic Activity Probabilities 05 Sep to 07 Sep
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 20% | 15% | 15% |
| Minor storm | 05% | 01% | 01% |
| Major-severe storm | 01% | 01% | 01% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 15% | 15% | 15% |
| Minor storm | 20% | 15% | 15% |
| Major-severe storm | 20% | 05% | 10% |
All times in UTC
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