Viewing archive of Thursday, 17 August 2017

Solar activity report

Report of Solar-Geophysical Activity 2017 Aug 17 2200 UTC
Prepared by the NOAA © SWPC and processed by

Joint USAF/NOAA Report of Solar and Geophysical Activity

SDF Number 229 Issued at 2200Z on 17 Aug 2017

IA. Analysis of Solar Active Regions and Activity from 16-2100Z to 17-2100Z

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 chance for a C-class flares and a slight chance for an M-class flare on days one and two (18 Aug, 19 Aug) and expected to be very low with a chance for a C-class flares on day three (20 Aug).
IIA. Geophysical Activity Summary 16-2100Z to 17-2100Z
The geomagnetic field has been at quiet to minor storm levels for the past 24 hours. Solar wind speed reached a peak of 594 km/s at 17/1851Z. Total IMF reached 13 nT at 17/0733Z. The maximum southward component of Bz reached -12 nT at 17/0820Z. Electrons greater than 2 MeV at geosynchronous orbit reached a peak level of 330 pfu.
IIB. Geophysical Activity Forecast
The geomagnetic field is expected to be at unsettled to minor storm levels on day one (18 Aug), quiet to active levels on day two (19 Aug) and unsettled to active levels on day three (20 Aug).
III. Event Probabilities 18 Aug to 20 Aug
Class M10%10%05%
Class X01%01%01%
IV. Penticton 10.7 cm Flux
  Observed       17 Aug 077
  Predicted   18 Aug-20 Aug 078/077/076
  90 Day Mean        17 Aug 076

V. Geomagnetic A Indices
  Observed Afr/Ap 16 Aug  005/006
  Estimated     Afr/Ap 17 Aug  023/033
  Predicted    Afr/Ap 18 Aug-20 Aug  019/024-015/018-012/016

VI. Geomagnetic Activity Probabilities 18 Aug to 20 Aug
A. Middle Latitudes
Minor storm25%15%15%
Major-severe storm05%01%01%
B. High Latitudes
Minor storm20%25%25%
Major-severe storm65%50%50%

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