Joint USAF/NOAA Report of Solar and Geophysical Activity 15 February 2011

:Product: Report of Solar-Geophysical Activity
:Issued: 2011 Feb 15 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 046 Issued at 2200Z on 15 Feb 2011
IA. Analysis of Solar Active Regions and Activity from 14/2100Z
to 15/2100Z: Solar activity has been high. Region 1158 (S21W27)
produced an X2 x-ray event at 15/0156Z associated with a Tenflare
and a Type II radio sweep. A halo CME was associated with this event
and had an estimated plane-of-sky speed around 710 km/s. Region 1158
has increased in area to 600 millionths and has a beta-gamma-delta
magnetic classification. This region also produced multiple C-class
events the largest being a C4 at 15/0432Z. New Region 1161 (N11E38)
has grown and is currently a magnetically simple D-type sunspot
group, but did not produce any flares.
IB. Solar Activity Forecast: Solar activity is expected to be
moderate with a chance for isolated high activity for the next three
days (16-18 February). Region 1158 is the most likely source for
activity.
IIA. Geophysical Activity Summary 14/2100Z to 15/2100Z:
The geomagnetic field has been predominately quiet with isolated
unsettled conditions to begin the period. Solar wind data from the
ACE satellite indicated a drop in total field to around 4nT as the
effects from yesterday’s transient subsided. GOES-13 indicated an
enhancement of the greater than 10MeV protons starting at 15/0710Z
and peaking around 2.6 PFU at geosynchronous orbit. Solar wind
velocities did increase slightly to around 500 km/s most likely due
to a favorably positioned coronal hole.
IIB. Geophysical Activity Forecast: The geomagnetic field is
expected to be quiet to unsettled on day one (16 February). Day two
(17 February) is expected to be quiet to active with a chance for
minor storming late in the period. Day three (18 February) is
expected to be unsettled to active with a chance for minor
storming. The increase in activity is forecast due to expected
arrival of the CME from the X2 event described in part IA.
III. Event Probabilities 16 Feb-18 Feb
Class M 60/60/60
Class X 20/20/20
Proton 15/15/15
PCAF Green
IV. Penticton 10.7 cm Flux
Observed 15 Feb 113
Predicted 16 Feb-18 Feb 103/100/100
90 Day Mean 15 Feb 084
V. Geomagnetic A Indices
Observed Afr/Ap 14 Feb 006/010
Estimated Afr/Ap 15 Feb 004/006
Predicted Afr/Ap 16 Feb-18 Feb 008/010-018/018-025/025
VI. Geomagnetic Activity Probabilities 16 Feb-18 Feb
A. Middle Latitudes
Active 15/25/35
Minor storm 01/15/20
Major-severe storm 01/01/05
B. High Latitudes
Active 20/45/45
Minor storm 05/25/25
Major-severe storm 00/05/05