Viewing archive of Saturday, 9 July 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 Jul 09 2200 UTC
Prepared by the NOAA © SWPC and processed by SpaceWeatherLive.com

Joint USAF/NOAA Report of Solar and Geophysical Activity

SDF Number 190 Issued at 2200Z on 09 Jul 2011

IA. Analysis of Solar Active Regions and Activity from 08-2100Z to 09-2100Z

Solar activity has been at very low levels for the past 24 hours. Region 1247 (S18W02) produced the largest event of the period, a B4 x-ray event at 09/0028Z. A nearby filament eruption was associated with this event with a subsequent partial-halo asymmetric CME, first visible in LASCO C2 imagery at 09/0125Z. This CME does have an earth directed component. Region 1249 (S16E25) was numbered early in the period but like many of the numbered regions on the disk, has remained stable.
IB. Solar Activity Forecast
Solar activity is expected to be at very low to low levels for the next three days (10-12 July).
IIA. Geophysical Activity Summary 08-2100Z to 09-2100Z
The geomagnetic field has been at quiet to active levels of the past 24 hours. The elevated activity was due to a solar sector boundary (SSB) crossing early in the period. Measurements by the ACE spacecraft indicate the onset of a coronal hole high speed stream (CH HSS) with solar wind speeds increasing, from 350 km/s to around 450 km/s.
IIB. Geophysical Activity Forecast
The geomagnetic field is expected to be at quiet to unsettled levels for the next two days (10-11 July) as a CH HSS continues to be geoeffective. On day three (12 July), coupled with the arrival of another CH HSS, the CME, observed earlier today, is expected to impact Earth. Since this CME was only a partial-halo and is not traveling at great speed, only unsettled to active levels are expected.
III. Event Probabilities 10 Jul to 12 Jul
Class M05%05%05%
Class X01%01%01%
Proton01%01%01%
PCAFGreen
IV. Penticton 10.7 cm Flux
  Observed       09 Jul 086
  Predicted   10 Jul-12 Jul  086/086/088
  90 Day Mean        09 Jul 099
V. Geomagnetic A Indices
  Observed Afr/Ap 08 Jul  006/008
  Estimated     Afr/Ap 09 Jul  010/010
  Predicted    Afr/Ap 10 Jul-12 Jul  007/007-007/007-012/012
VI. Geomagnetic Activity Probabilities 10 Jul to 12 Jul
A. Middle Latitudes
Active20%20%30%
Minor storm05%05%10%
Major-severe storm01%01%01%
B. High Latitudes
Active25%25%40%
Minor storm05%05%10%
Major-severe storm01%01%01%

All times in UTC

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