Solar activity report

Viewing archive of Friday, 25 September 2015

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 2015 Sep 25 2200 UTC
Prepared by the NOAA © SWPC and processed by SpaceWeatherLive.com

Joint USAF/NOAA Report of Solar and Geophysical Activity

SDF Number 268 Issued at 2200Z on 25 Sep 2015

IA. Analysis of Solar Active Regions and Activity from 24-2100Z to 25-2100Z

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 24/2347Z from Region 2418 (S16W77). There are currently 8 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 (26 Sep, 27 Sep, 28 Sep).

IIA. Geophysical Activity Summary 24-2100Z to 25-2100Z

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 549 km/s at 25/0050Z. Total IMF reached 7 nT at 25/0217Z. The maximum southward component of Bz reached -5 nT at 25/1007Z. Electrons greater than 2 MeV at geosynchronous orbit reached a peak level of 636 pfu.

IIB. Geophysical Activity Forecast

The geomagnetic field is expected to be at quiet to active levels on day one (26 Sep), quiet to unsettled levels on day two (27 Sep) and quiet levels on day three (28 Sep).

III. Event Probabilities 26 Sep to 28 Sep

Class M	35%	35%	35%
Class X	01%	01%	01%
Proton	01%	01%	01%
PCAF	green

IV. Penticton 10.7 cm Flux

  Observed       25 Sep 120
  Predicted   26 Sep-28 Sep 115/110/115
  90 Day Mean        25 Sep 104

V. Geomagnetic A Indices

  Observed Afr/Ap 24 Sep  008/010
  Estimated     Afr/Ap 25 Sep  009/010
  Predicted    Afr/Ap 26 Sep-28 Sep  013/015-007/008-007/008

VI. Geomagnetic Activity Probabilities 26 Sep to 28 Sep

A. Middle Latitudes
Active	30%	10%	10%
Minor storm	10%	01%	01%
Major-severe storm	01%	01%	01%

B. High Latitudes
Active	15%	20%	20%
Minor storm	30%	25%	25%
Major-severe storm	40%	20%	20%

All times in UTC

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