Viewing archive of Wednesday, 5 October 2011

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 2011 Oct 05 2200 UTC
Prepared by the NOAA © SWPC and processed by

Joint USAF/NOAA Report of Solar and Geophysical Activity

SDF Number 278 Issued at 2200Z on 05 Oct 2011

IA. Analysis of Solar Active Regions and Activity from 04-2100Z to 05-2100Z

Solar activity for the past 24 hours has been at low levels. New Region 1313 (S13E65) rotated onto the southeast limb early in the period and has been responsible for a majority of the activity. Region 1313, produced the largest event of the period, a C9/Sf flare at 05/1242Z. Multiple CMEs were observed during the past 24 hours, but none of them were considered to be geoeffective.
IB. Solar Activity Forecast
Solar activity is expected to be at low to moderate levels for the next three days (06-08 October) as Region 1313 continues to evolve.
IIA. Geophysical Activity Summary 04-2100Z to 05-2100Z
The geomagnetic field has been at quiet to minor storm levels during the past 24 hours. At 05/0742, a Sudden Impulse (SI) of 19 nT was observed by the Boulder magnetometer. Following this SI, solar wind speeds, as measured by the ACE spacecraft, increased from 370 km/s to around 480 km/s. The IMF also increased to around 12 nT, with some extended periods of southward Bz. These characteristics are congruent with the arrival of a CME. The greater than 2 MeV electron flux at geosynchronous orbit reached high levels during the period.
IIB. Geophysical Activity Forecast
The geomagnetic field is expected to remain at unsettled to active levels with a chance for minor storm periods on day one (06 October). Predominantly quiet to unsettled levels are expected for days two and three (07-08 October) as the effects of the CMEs wane.
III. Event Probabilities 06 Oct to 08 Oct
Class M40%40%40%
Class X01%01%01%
IV. Penticton 10.7 cm Flux
  Observed       05 Oct 127
  Predicted   06 Oct-08 Oct  125/125/130
  90 Day Mean        05 Oct 113
V. Geomagnetic A Indices
  Observed Afr/Ap 04 Oct  004/006
  Estimated     Afr/Ap 05 Oct  015/018
  Predicted    Afr/Ap 06 Oct-08 Oct  015/015-008/008-008/008
VI. Geomagnetic Activity Probabilities 06 Oct to 08 Oct
A. Middle Latitudes
Minor storm25%05%05%
Major-severe storm05%01%01%
B. High Latitudes
Minor storm30%10%10%
Major-severe storm05%01%01%

All times in UTC

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