Viewing archive of Wednesday, 18 September 2013

Solar activity report

Report of Solar-Geophysical Activity 2013 Sep 18 2200 UTC
Prepared by the NOAA © SWPC and processed by

Joint USAF/NOAA Report of Solar and Geophysical Activity

SDF Number 261 Issued at 2200Z on 18 Sep 2013

IA. Analysis of Solar Active Regions and Activity from 17-2100Z to 18-2100Z

Solar activity has been at low levels for the past 24 hours. The largest solar event of the period was a C3 event observed at 18/0315Z from Region 1846 (S17E62). There are currently 5 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 (19 Sep, 20 Sep, 21 Sep).
IIA. Geophysical Activity Summary 17-2100Z to 18-2100Z
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 570 km/s at 18/2019Z. Total IMF reached 10 nT at 18/1335Z. The maximum southward component of Bz reached -5 nT at 18/1531Z.
IIB. Geophysical Activity Forecast
The geomagnetic field is expected to be at quiet to unsettled levels on days one and two (19 Sep, 20 Sep) and quiet levels on day three (21 Sep).
III. Event Probabilities 19 Sep to 21 Sep
Class M05%05%05%
Class X01%01%01%
IV. Penticton 10.7 cm Flux
  Observed       18 Sep 104
  Predicted   19 Sep-21 Sep 105/105/110
  90 Day Mean        18 Sep 112

V. Geomagnetic A Indices
  Observed Afr/Ap 17 Sep  008/009
  Estimated     Afr/Ap 18 Sep  007/008
  Predicted    Afr/Ap 19 Sep-21 Sep  007/008-007/008-005/005

VI. Geomagnetic Activity Probabilities 19 Sep to 21 Sep
A. Middle Latitudes
Minor storm01%01%01%
Major-severe storm01%01%01%
B. High Latitudes
Minor storm25%25%15%
Major-severe storm10%10%05%

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