Viewing archive of Tuesday, 11 September 2018

Solar activity report

Report of Solar-Geophysical Activity 2018 Sep 11 2200 UTC
Prepared by the NOAA © SWPC and processed by

Joint USAF/NOAA Report of Solar and Geophysical Activity

SDF Number 254 Issued at 2200Z on 11 Sep 2018

IA. Analysis of Solar Active Regions and Activity from 10-2100Z to 11-2100Z

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 slight chance for a C-class flare on days one and two (12 Sep, 13 Sep) and expected to be very low on day three (14 Sep).
IIA. Geophysical Activity Summary 10-2100Z to 11-2100Z
The geomagnetic field has been at unsettled to major storm levels for the past 24 hours. Solar wind speed reached a peak of 623 km/s at 11/1825Z. Total IMF reached 15 nT at 10/2142Z. The maximum southward component of Bz reached -13 nT at 10/2135Z. Electrons greater than 2 MeV at geosynchronous orbit reached a peak level of 366 pfu.
IIB. Geophysical Activity Forecast
The geomagnetic field is expected to be at quiet to minor storm levels on day one (12 Sep) and quiet to active levels on days two and three (13 Sep, 14 Sep).
III. Event Probabilities 12 Sep to 14 Sep
Class M01%01%01%
Class X01%01%01%
IV. Penticton 10.7 cm Flux
  Observed       11 Sep 069
  Predicted   12 Sep-14 Sep 070/070/069
  90 Day Mean        11 Sep 070

V. Geomagnetic A Indices
  Observed Afr/Ap 10 Sep  015/016
  Estimated     Afr/Ap 11 Sep  028/043
  Predicted    Afr/Ap 12 Sep-14 Sep  012/016-011/012-010/012

VI. Geomagnetic Activity Probabilities 12 Sep to 14 Sep
A. Middle Latitudes
Minor storm25%20%15%
Major-severe storm10%05%05%
B. High Latitudes
Minor storm25%25%25%
Major-severe storm60%55%45%

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