Viewing archive of Thursday, 21 May 2015

Solar activity report

Report of Solar-Geophysical Activity 2015 May 21 2200 UTC
Prepared by the NOAA © SWPC and processed by

Joint USAF/NOAA Report of Solar and Geophysical Activity

SDF Number 141 Issued at 2200Z on 21 May 2015

IA. Analysis of Solar Active Regions and Activity from 20-2100Z to 21-2100Z

Solar activity has been at low levels for the past 24 hours. The largest solar event of the period was a C1 event observed at 21/0706Z from Region 2349 (S21W10). There are currently 3 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 (22 May, 23 May, 24 May).
IIA. Geophysical Activity Summary 20-2100Z to 21-2100Z
The geomagnetic field has been at quiet levels for the past 24 hours. Solar wind speed, as measured by the ACE spacecraft, reached a peak speed of 468 km/s at 21/1022Z. Total IMF reached 6 nT at 20/2106Z. The maximum southward component of Bz reached -3 nT at 21/1130Z. Electrons greater than 2 MeV at geosynchronous orbit reached a peak level of 146 pfu.
IIB. Geophysical Activity Forecast
The geomagnetic field is expected to be at quiet levels on days one, two, and three (22 May, 23 May, 24 May).
III. Event Probabilities 22 May to 24 May
Class M01%01%01%
Class X01%01%01%
IV. Penticton 10.7 cm Flux
  Observed       21 May 102
  Predicted   22 May-24 May 100/100/100
  90 Day Mean        21 May 128

V. Geomagnetic A Indices
  Observed Afr/Ap 20 May  010/009
  Estimated     Afr/Ap 21 May  003/004
  Predicted    Afr/Ap 22 May-24 May  006/005-006/005-006/005

VI. Geomagnetic Activity Probabilities 22 May to 24 May
A. Middle Latitudes
Minor storm01%01%01%
Major-severe storm01%01%01%
B. High Latitudes
Minor storm20%20%20%
Major-severe storm10%10%10%

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