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Viewing archive of Tuesday, 31 July 2012

Solar activity report

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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 2012 Jul 31 2200 UTC
Prepared by the NOAA © SWPC and processed by SpaceWeatherLive.com

Joint USAF/NOAA Report of Solar and Geophysical Activity

SDF Number 213 Issued at 2200Z on 31 Jul 2012

IA. Analysis of Solar Active Regions and Activity from 30-2100Z to 31-2100Z

Solar activity was low. The largest of the C-class flares were an impulsive C6 at 31/0000Z from new Region 1538 (S23E68) and a long-duration C5 at 31/1130Z from Region 1535 (N18E51). Both flares had associated Type II (estimated speeds of 730 and 880 km/s, respectively) and Type IV radio sweeps along with coronal mass ejections seen off the East limb in SOHO/LASCO C2 imagery. Another CME was observed in SOHO/LASCO C2 imagery off the southwest limb associated with a filament eruption seen in SDO/AIA 171 imagery at 31/0846Z. None of the CMEs are expected to be geoeffective. New Region 1537 (N12E76) rotated onto the northeast limb and was numbered today.
IB. Solar Activity Forecast
Solar activity is expected to be low with a chance for M-class flares.
IIA. Geophysical Activity Summary 30-2100Z to 31-2100Z
The geomagnetic field was quiet.
IIB. Geophysical Activity Forecast
The geomagnetic field is expected to be mostly quiet on day 1 (01 August). On day 2 (02 August), geomagnetic activity is expected to be at quiet to unsettled levels with possible isolated active periods due to effects from the 28 July CME. Conditions are expected to be quiet to unsettled on day 3 (03 August).
III. Event Probabilities 01 Aug to 03 Aug
Class M35%35%35%
Class X05%05%05%
Proton05%05%05%
PCAFGreen
IV. Penticton 10.7 cm Flux
  Observed       31 Jul 140
  Predicted   01 Aug-03 Aug  140/145/150
  90 Day Mean        31 Jul 126
V. Geomagnetic A Indices
  Observed Afr/Ap 30 Jul  011/015
  Estimated     Afr/Ap 31 Jul  006/006
  Predicted    Afr/Ap 01 Aug-03 Aug  006/005-008/010-007/008
VI. Geomagnetic Activity Probabilities 01 Aug to 03 Aug
A. Middle Latitudes
Active05%20%15%
Minor storm01%10%05%
Major-severe storm01%01%01%
B. High Latitudes
Active15%15%15%
Minor storm15%25%20%
Major-severe storm05%30%20%

All times in UTC

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Current data suggests there is a moderate possibility for aurora to appear at the following high latitude regions in the near future

Gillam, MB, Yellowknife, NT

Current data suggests there is a slight possibility for aurora to appear at the following high latitude regions in the near future

Edmonton, AB, Iqaluit, NU, Saskatoon, SK
Nuuk
Reykjavik
The strength of the interplanetary magnetic field is moderate (10.33nT), the direction is slightly South (-6.06nT).

S1 - Minor solar radiation storm

Minor impacts on HF radio through polar regions

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