Joint USAF/NOAA Report of Solar and Geophysical Activity 13 April 2011

:Product: Report of Solar-Geophysical Activity
:Issued: 2011 Apr 13 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 103 Issued at 2200Z on 13 Apr 2011
IA. Analysis of Solar Active Regions and Activity from 12/2100Z
to 13/2100Z: Solar activity was low during the past 24 hours. The
majority of the C-class activity originated from Regions 1191
(N08E56) and 1193 (N17E71). Region 1190 (N12W00) continues to be the
most complex as an Eac-type group with a beta-gamma magnetic
configuration, but has not produced much activity. Region 1193 was
numbered today as it rotated onto the east limb and is a Dao-type
group with a beta magnetic configuration.
IB. Solar Activity Forecast: Solar activity is expected to be low
with the chance for M-class activity increasing during the next
three days (14-16 April) as new Region 1193 continues to rotate onto
the disk.
IIA. Geophysical Activity Summary 12/2100Z to 13/2100Z:
The geomagnetic field was unsettled to active with major storm
periods observed at high latitudes during the past 24 hours. The
activity was the result of elevated wind speeds associated with a
coronal hole high speed stream (CH HSS).
IIB. Geophysical Activity Forecast: The geomagnetic field is
expected to be quiet to unsettled with a chance for isolated active
periods on day one (14 April) due to residual effects from the CH
HSS. Mostly quiet conditions are expected for days two and three
(15-16 April) as the effects from the CH HSS wane.
III. Event Probabilities 14 Apr-16 Apr
Class M 15/15/15
Class X 01/01/01
Proton 01/01/01
PCAF Green
IV. Penticton 10.7 cm Flux
Observed 13 Apr 118
Predicted 14 Apr-16 Apr 120/120/120
90 Day Mean 13 Apr 102
V. Geomagnetic A Indices
Observed Afr/Ap 12 Apr 014/023
Estimated Afr/Ap 13 Apr 012/012
Predicted Afr/Ap 14 Apr-16 Apr 005/005-005/005-005/005
VI. Geomagnetic Activity Probabilities 14 Apr-16 Apr
A. Middle Latitudes
Active 05/05/05
Minor storm 01/01/01
Major-severe storm 01/01/01
B. High Latitudes
Active 05/05/05
Minor storm 01/01/01
Major-severe storm 01/01/01