Joint USAF/NOAA Report of Solar and Geophysical Activity 20 February 2012

:Product: Report of Solar-Geophysical Activity
:Issued: 2012 Feb 20 2200 UTC
# Prepared jointly by the U.S. Dept. of Commerce, NOAA,
# Space Weather Prediction Center and the U.S. Air Force.
#
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 051 Issued at 2200Z on 20 Feb 2012
IA. Analysis of Solar Active Regions and Activity from 19/2100Z
to 20/2100Z: Solar activity was low. There were three C-class flares
during the past 24 hours. The largest of these was a C4/Sf at 0509Z
from Region 1421 (N18E32). Region 1422 (N16W11) produced the other
two C-flares and is currently the largest group on the disk.
IB. Solar Activity Forecast: Solar activity is expected to be low.
IIA. Geophysical Activity Summary 19/2100Z to 20/2100Z:
The geomagnetic field was unsettled to active with some isolated
storm periods at high latitudes. Solar wind data from ACE indicated
the influence of a high speed stream from a coronal hole. The
greater than 2 MeV electron flux at geosynchronous orbit reached
high levels during the period.
IIB. Geophysical Activity Forecast: The geomagnetic field is
expected to be unsettled with a chance for active periods on the
first day (21 Feb) due to continued effects from the high speed
stream. A decrease to mostly quiet levels is predicted for the
second day (22 Feb) and quiet levels are expected to continue for
the third day (23 Feb).
III. Event Probabilities 21 Feb-23 Feb
Class M 10/10/10
Class X 01/01/01
Proton 01/01/01
PCAF green
IV. Penticton 10.7 cm Flux
Observed 20 Feb 111
Predicted 21 Feb-23 Feb 110/110/110
90 Day Mean 20 Feb 131
V. Geomagnetic A Indices
Observed Afr/Ap 19 Feb 011/016
Estimated Afr/Ap 20 Feb 016/018
Predicted Afr/Ap 21 Feb-23 Feb 008/010-006/008-005/005
VI. Geomagnetic Activity Probabilities 21 Feb-23 Feb
A. Middle Latitudes
Active 10/05/05
Minor storm 01/01/01
Major-severe storm 01/01/01
B. High Latitudes
Active 15/15/15
Minor storm 20/10/10
Major-severe storm 10/05/05