Viewing archive of Tuesday, 12 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 12 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 255 Issued at 2200Z on 12 Sep 2017IA. Analysis of Solar Active Regions and Activity from 11-2100Z to 12-2100Z
Solar activity has been at very low levels for the past 24
hours. There are currently 1 numbered sunspot regions on the disk.
IB. Solar Activity Forecast
Solar activity is expected to be very low
with a chance for a C-class flares on days one, two, and three (13 Sep,
14 Sep, 15 Sep).
IIA. Geophysical Activity Summary 11-2100Z to 12-2100Z
The geomagnetic
field has been at quiet to unsettled levels for the past 24 hours. Solar
wind speed reached a peak of 652 km/s at 12/2050Z. Total IMF reached 16
nT at 12/2054Z. The maximum southward component of Bz reached -10 nT at
12/1954Z. Protons greater than 10 MeV at geosynchronous orbit reached a
peak level of 872 pfu at 11/2105Z. Protons greater than 100 MeV at
geosynchronous orbit reached a peak level of 10 pfu at 11/2115Z.
Electrons greater than 2 MeV at geosynchronous orbit reached a peak
level of 7042 pfu.
IIB. Geophysical Activity Forecast
The geomagnetic field is expected
to be at active to major storm levels on day one (13 Sep), unsettled to
minor storm levels on day two (14 Sep) and active to minor storm levels
on day three (15 Sep). Protons are expected to cross threshold on day
one (13 Sep), are expected to cross threshold on day two (14 Sep) and
are likely to cross threshold on day three (15 Sep).
III. Event Probabilities 13 Sep to 15 Sep
| Class M | 01% | 01% | 01% |
| Class X | 01% | 01% | 01% |
| Proton | 95% | 80% | 60% |
| PCAF | red | ||
IV. Penticton 10.7 cm Flux
Observed 12 Sep 076 Predicted 13 Sep-15 Sep 075/075/075 90 Day Mean 12 Sep 081
V. Geomagnetic A Indices
Observed Afr/Ap 11 Sep 008/010 Estimated Afr/Ap 12 Sep 010/013 Predicted Afr/Ap 13 Sep-15 Sep 024/036-025/032-021/030
VI. Geomagnetic Activity Probabilities 13 Sep to 15 Sep
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 25% | 30% | 30% |
| Minor storm | 35% | 30% | 25% |
| Major-severe storm | 20% | 15% | 15% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 05% | 05% | 05% |
| Minor storm | 20% | 20% | 20% |
| Major-severe storm | 75% | 65% | 65% |
All times in UTC
Current data suggests there is a slight possibility for aurora to appear at the following high latitude regions in the near future
Whitehorse, YT, Yellowknife, NTAnchorage, AK, Fairbanks, AK, Juneau, AK, Utqiagvik, AK
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