Viewing archive of Friday, 13 April 2012

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 2012 Apr 13 2200 UTC
Prepared by the NOAA © SWPC and processed by SpaceWeatherLive.com

Joint USAF/NOAA Report of Solar and Geophysical Activity

SDF Number 104 Issued at 2200Z on 13 Apr 2012

IA. Analysis of Solar Active Regions and Activity from 12-2100Z to 13-2100Z

Solar activity was very low. Region 1455 (N07W19) produced occasional B-class x-ray flares. It showed gradual spot and penumbral growth during the period as well as a mix of polarities in its intermediate and trailer portions, which indicated a beta-gamma magnetic structure. New Region 1457 (N22E41) was numbered.
IB. Solar Activity Forecast
Solar activity is expected to be very low during days 1 - 3 (14 - 16 April) with a chance for isolated C-class flares from Region 1455.
IIA. Geophysical Activity Summary 12-2100Z to 13-2100Z
Geomagnetic field activity ranged from quiet to minor storm levels with a brief period of major storm at high latitudes. The increased field activity was associated with a persistent coronal hole high-speed stream (CH HSS). Solar winds speeds gradually increased during the first half of the period (maximum speed 693 km/s at 13/0846Z), then gradually decreased during the second half of the period (minimum speed 544 km/s at 13/1941Z).
IIB. Geophysical Activity Forecast
Geomagnetic field activity is expected to be at quiet to unsettled levels during days 1 - 2 (14 - 15 April) with a chance for active levels due to persistent CH HSS effects. Activity is expected to decrease to mostly quiet levels on day 3 (16 April) as the CH HSS subsides.
III. Event Probabilities 14 Apr to 16 Apr
Class M05%05%05%
Class X01%01%01%
Proton01%01%01%
PCAFgreen
IV. Penticton 10.7 cm Flux
  Observed       13 Apr 098
  Predicted   14 Apr-16 Apr  100/100/100
  90 Day Mean        13 Apr 114
V. Geomagnetic A Indices
  Observed Afr/Ap 12 Apr  011/014
  Estimated     Afr/Ap 13 Apr  014/020
  Predicted    Afr/Ap 14 Apr-16 Apr  007/012-010/012-004/005
VI. Geomagnetic Activity Probabilities 14 Apr to 16 Apr
A. Middle Latitudes
Active30%25%15%
Minor storm20%15%05%
Major-severe storm01%01%01%
B. High Latitudes
Active35%30%20%
Minor storm25%20%10%
Major-severe storm01%01%01%

All times in UTC

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

Oulu, Rovaniemi, Sodankylä, Utsjoki
Reykjavik
Kirkenes, Tromsø, Trondheim
Murmansk, Vorkuta
Kiruna, Luleå
The Disturbance Storm Time index predicts moderate storm conditions right now (-50nT)
A transequatorial coronal hole was detected in an earth-facing position on Monday, 24 March 2025

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