Viewing archive of Saturday, 16 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 16 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 259 Issued at 2200Z on 16 Sep 2017IA. Analysis of Solar Active Regions and Activity from 15-2100Z to 16-2100Z
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
on days one, two, and three (17 Sep, 18 Sep, 19 Sep).
IIA. Geophysical Activity Summary 15-2100Z to 16-2100Z
The geomagnetic
field has been at unsettled to major storm levels for the past 24 hours.
Solar wind speed reached a peak of 821 km/s at 16/1435Z. Total IMF
reached 8 nT at 16/0356Z. The maximum southward component of Bz reached
-7 nT at 16/0345Z. Protons greater than 10 MeV at geosynchronous orbit
reached a peak level of 2 pfu at 16/0145Z. Electrons greater than 2 MeV
at geosynchronous orbit reached a peak level of 22886 pfu.
IIB. Geophysical Activity Forecast
The geomagnetic field is expected
to be at quiet to minor storm levels on day one (17 Sep) and quiet to
active levels on days two and three (18 Sep, 19 Sep).
III. Event Probabilities 17 Sep to 19 Sep
| Class M | 01% | 01% | 01% |
| Class X | 01% | 01% | 01% |
| Proton | 01% | 01% | 01% |
| PCAF | green | ||
IV. Penticton 10.7 cm Flux
Observed 16 Sep 072 Predicted 17 Sep-19 Sep 072/075/075 90 Day Mean 16 Sep 081
V. Geomagnetic A Indices
Observed Afr/Ap 15 Sep 030/041 Estimated Afr/Ap 16 Sep 024/031 Predicted Afr/Ap 17 Sep-19 Sep 016/020-012/015-011/012
VI. Geomagnetic Activity Probabilities 17 Sep to 19 Sep
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 35% | 30% | 25% |
| Minor storm | 20% | 10% | 10% |
| Major-severe storm | 05% | 01% | 01% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 10% | 15% | 15% |
| Minor storm | 25% | 25% | 30% |
| Major-severe storm | 60% | 40% | 40% |
All times in UTC
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