Viewing archive of Friday, 27 April 2012

Solar activity report

Report of Solar-Geophysical Activity 2012 Apr 27 2200 UTC
Prepared by the NOAA © SWPC and processed by

Joint USAF/NOAA Report of Solar and Geophysical Activity

SDF Number 118 Issued at 2200Z on 27 Apr 2012

IA. Analysis of Solar Active Regions and Activity from 26-2100Z to 27-2100Z

Solar activity was at moderate levels due to an M1/1n flare at 27/0824Z from Region 1466 (N11W38). Other activity consisted of single, low-level C-class flares from Regions 1459 (S19W88), 1465 (S17W53), 1467 (N11E32), 1469 (S24E28) and 1466. During the period, Region 1465 developed into a beta-gamma-delta magnetic configuration while the remaining regions showed little change. Numerous non-Earth directed CMEs were observed off the SW limb over the past 24 hours, all originating from old Region 1462 (S25, L=139) which rotated around the west on 24 April.
IB. Solar Activity Forecast
Solar activity is expected to be low with a slight chance for M-class activity for the next three days (28 - 30 April).
IIA. Geophysical Activity Summary 26-2100Z to 27-2100Z
The geomagnetic field was at quiet to unsettled levels. Through the period, ACE solar wind velocities steadily decreased from about 560 km/s to near 500km/s while the Bz component of the interplanetary magnetic field was variable between +/-4 nT. The greater than 2 MeV electron flux at geosynchronous orbit was at high levels throughout the period.
IIB. Geophysical Activity Forecast
The geomagnetic field is expected to be at predominately quiet levels for the next three days (28 - 30 April).
III. Event Probabilities 28 Apr to 30 Apr
Class M20%20%20%
Class X01%01%01%
IV. Penticton 10.7 cm Flux
  Observed       27 Apr 118
  Predicted   28 Apr-30 Apr  115/110/110
  90 Day Mean        27 Apr 112
V. Geomagnetic A Indices
  Observed Afr/Ap 26 Apr  017/020
  Estimated     Afr/Ap 27 Apr  006/008
  Predicted    Afr/Ap 28 Apr-30 Apr  004/005-004/005-004/005
VI. Geomagnetic Activity Probabilities 28 Apr to 30 Apr
A. Middle Latitudes
Minor storm01%01%01%
Major-severe storm01%01%01%
B. High Latitudes
Minor storm01%01%01%
Major-severe storm01%10%01%

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