Viewing archive of Monday, 18 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 18 2200 UTC
Prepared by the NOAA © SWPC and processed by

Joint USAF/NOAA Report of Solar and Geophysical Activity

SDF Number 261 Issued at 2200Z on 18 Sep 2017

IA. Analysis of Solar Active Regions and Activity from 17-2100Z to 18-2100Z

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 (19 Sep, 20 Sep, 21 Sep).
IIA. Geophysical Activity Summary 17-2100Z to 18-2100Z
The geomagnetic field has been at quiet to minor storm levels for the past 24 hours. Solar wind speed reached a peak of 707 km/s at 18/1034Z. Total IMF reached 7 nT at 17/2101Z. The maximum southward component of Bz reached -5 nT at 18/0056Z. Electrons greater than 2 MeV at geosynchronous orbit reached a peak level of 31067 pfu.
IIB. Geophysical Activity Forecast
The geomagnetic field is expected to be at quiet to active levels on days one and two (19 Sep, 20 Sep) and quiet to unsettled levels on day three (21 Sep).
III. Event Probabilities 19 Sep to 21 Sep
Class M01%01%01%
Class X01%01%01%
IV. Penticton 10.7 cm Flux
  Observed       18 Sep 072
  Predicted   19 Sep-21 Sep 072/072/073
  90 Day Mean        18 Sep 081

V. Geomagnetic A Indices
  Observed Afr/Ap 17 Sep  013/016
  Estimated     Afr/Ap 18 Sep  019/024
  Predicted    Afr/Ap 19 Sep-21 Sep  012/014-011/012-007/008

VI. Geomagnetic Activity Probabilities 19 Sep to 21 Sep
A. Middle Latitudes
Minor storm15%10%05%
Major-severe storm01%01%01%
B. High Latitudes
Minor storm25%25%25%
Major-severe storm50%40%30%

All times in UTC

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