Viewing archive of Thursday, 31 May 2018

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 2018 May 31 2200 UTC
Prepared by the NOAA © SWPC and processed by

Joint USAF/NOAA Report of Solar and Geophysical Activity

SDF Number 151 Issued at 2200Z on 31 May 2018

IA. Analysis of Solar Active Regions and Activity from 30-2100Z to 31-2100Z

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 on days one, two, and three (01 Jun, 02 Jun, 03 Jun).
IIA. Geophysical Activity Summary 30-2100Z to 31-2100Z
The geomagnetic field has been at quiet to active levels for the past 24 hours. Solar wind speed reached a peak of 498 km/s at 31/2100Z. Total IMF reached 17 nT at 31/1645Z. The maximum southward component of Bz reached -11 nT at 31/1705Z. Electrons greater than 2 MeV at geosynchronous orbit reached a peak level of 579 pfu.
IIB. Geophysical Activity Forecast
The geomagnetic field is expected to be at unsettled to minor storm levels on days one and two (01 Jun, 02 Jun) and quiet to active levels on day three (03 Jun).
III. Event Probabilities 01 Jun to 03 Jun
Class M01%01%01%
Class X01%01%01%
IV. Penticton 10.7 cm Flux
  Observed       31 May 077
  Predicted   01 Jun-03 Jun 077/077/077
  90 Day Mean        31 May 070

V. Geomagnetic A Indices
  Observed Afr/Ap 30 May  005/004
  Estimated     Afr/Ap 31 May  011/014
  Predicted    Afr/Ap 01 Jun-03 Jun  018/025-019/025-011/015

VI. Geomagnetic Activity Probabilities 01 Jun to 03 Jun
A. Middle Latitudes
Minor storm25%25%15%
Major-severe storm05%05%05%
B. High Latitudes
Minor storm25%25%25%
Major-severe storm55%55%45%

All times in UTC

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