Viewing archive of Saturday, 12 September 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 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 2015IA. Analysis of Solar Active Regions and Activity from 11-2100Z to 12-2100Z
Solar activity has been at low levels for the past 24 hours.
The largest solar event of the period was a C1 event observed at
11/2137Z from Region 2414 (S10W20). There are currently 6 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 and a slight chance for an M-class
flare 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 active levels for the past 24 hours. Solar
wind speed, as measured by the ACE spacecraft, reached a peak speed of
658 km/s at 12/0023Z. Total IMF reached 8 nT at 11/2113Z. The maximum
southward component of Bz reached -7 nT at 11/2134Z. Electrons greater
than 2 MeV at geosynchronous orbit reached a peak level of 10410 pfu.
IIB. Geophysical Activity Forecast
The geomagnetic field is expected
to be at unsettled to minor storm levels on days one and three (13 Sep,
15 Sep) and quiet to active levels on day two (14 Sep).
III. Event Probabilities 13 Sep to 15 Sep
| Class M | 10% | 10% | 10% |
| Class X | 01% | 01% | 01% |
| Proton | 01% | 01% | 01% |
| PCAF | green | ||
IV. Penticton 10.7 cm Flux
Observed 12 Sep 099 Predicted 13 Sep-15 Sep 100/105/105 90 Day Mean 12 Sep 107
V. Geomagnetic A Indices
Observed Afr/Ap 11 Sep 036/053 Estimated Afr/Ap 12 Sep 023/030 Predicted Afr/Ap 13 Sep-15 Sep 019/025-012/015-016/020
VI. Geomagnetic Activity Probabilities 13 Sep to 15 Sep
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 35% | 30% | 30% |
| Minor storm | 20% | 10% | 15% |
| Major-severe storm | 05% | 01% | 01% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 10% | 15% | 15% |
| Minor storm | 25% | 30% | 25% |
| Major-severe storm | 50% | 40% | 45% |
All times in UTC
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