Viewing archive of Monday, 21 September 2015

Solar activity report

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

Joint USAF/NOAA Report of Solar and Geophysical Activity

SDF Number 264 Issued at 2200Z on 21 Sep 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 C8 event observed at 21/0518Z from Region 2420 (N10E64). There are currently 4 numbered sunspot regions on the disk.
IB. Solar Activity Forecast
Solar activity is expected to be low with a chance for M-class flares on days one, two, and three (22 Sep, 23 Sep, 24 Sep).
IIA. Geophysical Activity Summary 20-2100Z to 21-2100Z
The geomagnetic field has been at quiet to unsettled levels for the past 24 hours. Solar wind speed, as measured by the ACE spacecraft, reached a peak speed of 660 km/s at 21/0649Z. Total IMF reached 8 nT at 21/0824Z. The maximum southward component of Bz reached -6 nT at 20/2152Z. Protons greater than 10 MeV at geosynchronous orbit reached a peak level of 2 pfu at 20/2105Z. Electrons greater than 2 MeV at geosynchronous orbit reached a peak level of 374 pfu.
IIB. Geophysical Activity Forecast
The geomagnetic field is expected to be at quiet to unsettled levels on days one and three (22 Sep, 24 Sep) and quiet to active levels on day two (23 Sep). Protons greater than 10 Mev have a slight chance of crossing threshold on day one (22 Sep).
III. Event Probabilities 22 Sep to 24 Sep
Class M40%30%25%
Class X05%05%05%
IV. Penticton 10.7 cm Flux
  Observed       21 Sep 103
  Predicted   22 Sep-24 Sep 105/105/110
  90 Day Mean        21 Sep 103

V. Geomagnetic A Indices
  Observed Afr/Ap 20 Sep  032/035
  Estimated     Afr/Ap 21 Sep  012/013
  Predicted    Afr/Ap 22 Sep-24 Sep  007/010-012/012-007/008

VI. Geomagnetic Activity Probabilities 22 Sep to 24 Sep
A. Middle Latitudes
Minor storm05%10%01%
Major-severe storm01%01%01%
B. High Latitudes
Minor storm30%25%25%
Major-severe storm30%35%20%

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