Joint USAF/NOAA Report of Solar and Geophysical Activity 17 February 2011

:Product: Report of Solar-Geophysical Activity
:Issued: 2011 Feb 17 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 048 Issued at 2200Z on 17 Feb 2011
IA. Analysis of Solar Active Regions and Activity from 16/2100Z
to 17/2100Z: Solar activity was low during the past 24 hours.
Region 1158 (S19W52) decayed in area but retained a beta-gamma-delta
magnetic classification. It produced several C-class events, the
largest of which was a C6 observed at 16/0146Z. Region 1161
exhibited slow growth and has an area of 140 millionths with a
beta-gamma magnetic classification.
IB. Solar Activity Forecast: Solar activity is expected to be
moderate with M-class activity likely and a slight chance for an
isolated X-class event for the next three days (18-20 February).
IIA. Geophysical Activity Summary 16/2100Z to 17/2100Z:
The geomagnetic field was quiet during the past 24 hours.
IIB. Geophysical Activity Forecast: The geomagnetic field is
expected to be active with a chance for isolated minor storm periods
for day one (18 February). This activity is due to the effects of
two CMEs; the first associated with an M6 event at 13/1735Z and the
second associated with an X2 event at 15/0156Z. Quiet to active
conditions are expected for day two (19 February) as the effects of
these disturbances wane. The geomagnetic field is expected to
return to mostly quiet conditions on day three (20 February).
III. Event Probabilities 18 Feb-20 Feb
Class M 50/50/50
Class X 10/10/10
Proton 10/10/10
PCAF Green
IV. Penticton 10.7 cm Flux
Observed 17 Feb 111
Predicted 18 Feb-20 Feb 110/110/105
90 Day Mean 17 Feb 085
V. Geomagnetic A Indices
Observed Afr/Ap 16 Feb 001/002
Estimated Afr/Ap 17 Feb 008/010
Predicted Afr/Ap 18 Feb-20 Feb 025/025-015/015-005/005
VI. Geomagnetic Activity Probabilities 18 Feb-20 Feb
A. Middle Latitudes
Active 35/30/05
Minor storm 20/10/01
Major-severe storm 05/01/01
B. High Latitudes
Active 35/35/05
Minor storm 20/10/01
Major-severe storm 05/01/01