Viewing archive of Thursday, 28 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 28 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 271 Issued at 2200Z on 28 Sep 2017IA. Analysis of Solar Active Regions and Activity from 27-2100Z to 28-2100Z
Solar activity has been at very low levels for the past 24
hours. There are currently 3 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 (29 Sep,
30 Sep, 01 Oct).
IIA. Geophysical Activity Summary 27-2100Z to 28-2100Z
The geomagnetic
field has been at active to severe storm levels for the past 24 hours.
Solar wind speed reached a peak of 752 km/s at 28/0846Z. Total IMF
reached 13 nT at 28/0108Z. The maximum southward component of Bz reached
-11 nT at 27/2128Z. Electrons greater than 2 MeV at geosynchronous orbit
reached a peak level of 3706 pfu.
IIB. Geophysical Activity Forecast
The geomagnetic field is expected
to be at unsettled to minor storm levels on day one (29 Sep) and quiet
to active levels on days two and three (30 Sep, 01 Oct).
III. Event Probabilities 29 Sep to 01 Oct
| Class M | 01% | 01% | 01% |
| Class X | 01% | 01% | 01% |
| Proton | 01% | 01% | 01% |
| PCAF | green | ||
IV. Penticton 10.7 cm Flux
Observed 28 Sep 091 Predicted 29 Sep-01 Oct 091/091/091 90 Day Mean 28 Sep 082
V. Geomagnetic A Indices
Observed Afr/Ap 27 Sep 024/037 Estimated Afr/Ap 28 Sep 043/061 Predicted Afr/Ap 29 Sep-01 Oct 021/028-014/018-011/014
VI. Geomagnetic Activity Probabilities 29 Sep to 01 Oct
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 35% | 30% | 30% |
| Minor storm | 30% | 15% | 15% |
| Major-severe storm | 05% | 01% | 01% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 10% | 10% | 15% |
| Minor storm | 20% | 30% | 25% |
| Major-severe storm | 60% | 50% | 50% |
All times in UTC
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