Viewing archive of Sunday, 17 April 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 Apr 17 2200 UTC
Prepared by the NOAA © SWPC and processed by SpaceWeatherLive.com

Joint USAF/NOAA Report of Solar and Geophysical Activity

SDF Number 107 Issued at 2200Z on 17 Apr 2011

IA. Analysis of Solar Active Regions and Activity from 16-2100Z to 17-2100Z

Solar activity remained at low levels. Region 1185 (N14, L=032) produced four C-class flares as it rotated off of the solar limb. Region 1193 (N16E19) continues to increase in areal coverage and maintains its beta-gamma magnetic configuration. Region 1190 (N14W53) showed decreases in both spot number and areal coverage, however, it retains its beta-gamma magnetic configuration.
IB. Solar Activity Forecast
Solar activity is expected to be at low levels, with C-class flares expected for the next three days (18-20). There remains a chance for M-class flares during the period.
IIA. Geophysical Activity Summary 16-2100Z to 17-2100Z
The geomagnetic field was at quiet levels.
IIB. Geophysical Activity Forecast
The geomagnetic field is expected to be at predominantly quiet levels on days one and two (18-19 April). Activity is expected to increase to quiet to unsettled levels on day three (20 April), with a chance for active levels as well as a slight chance for minor storm levels at high latitudes. The increase in activity is due to a coronal hole high-speed stream.
III. Event Probabilities 18 Apr to 20 Apr
Class M40%40%40%
Class X05%05%05%
Proton05%05%05%
PCAFGreen
IV. Penticton 10.7 cm Flux
  Observed       17 Apr 114
  Predicted   18 Apr-20 Apr  115/112/110
  90 Day Mean        17 Apr 103
V. Geomagnetic A Indices
  Observed Afr/Ap 16 Apr  002/004
  Estimated     Afr/Ap 17 Apr  003/005
  Predicted    Afr/Ap 18 Apr-20 Apr  005/005-005/005-010/010
VI. Geomagnetic Activity Probabilities 18 Apr to 20 Apr
A. Middle Latitudes
Active05%05%35%
Minor storm01%01%10%
Major-severe storm01%01%05%
B. High Latitudes
Active10%10%40%
Minor storm01%01%15%
Major-severe storm01%01%05%

All times in UTC

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