Joint USAF/NOAA Report of Solar and Geophysical Activity 15 August 2011 (Corrected)
:Product: Report of Solar-Geophysical Activity
:Issued: 2011 Aug 16 0404 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
:::::::::: CORRECTED COPY ::::::::::
SDF Number 227 Issued at 2200Z on 15 Aug 2011
IA. Analysis of Solar Active Regions and Activity from 14/2100Z
to 15/2100Z: Solar activity has been low. Newly assigned Region
1271 (N17E74) produced a C1 flare at 15/0454Z. A C3 flare at
15/1120Z originated from a region on the southeast limb, not yet on
the disk. Both regions produced several B-class flares.
IB. Solar Activity Forecast: Solar activity is expected to be very
low to low with C-class events likely.
IIA. Geophysical Activity Summary 14/2100Z to 15/2100Z:
The geomagnetic field was quiet to active during the past 24 hours
with a brief minor storm period at Boulder from 15/0000 – 0300Z,
under the continued influence of a coronal hole high speed stream.
ACE solar wind data indicated velocities up to 560 km/s, density up
to 9 p/cc, and the southward component of the IMF (Bz) down to -9
nT.
IIB. Geophysical Activity Forecast: The geomagnetic field is
expected to be quiet to unsettled with a chance for active
conditions on days 1 and 2 (16-17 Aug). Day 3 (18 Aug) is expected
to return to quiet levels as effects from the coronal hole high
speed stream begin to wane.
III. Event Probabilities 16 Aug-18 Aug
Class M 05/05/05
Class X 01/01/01
Proton 01/01/01
PCAF Green
IV. Penticton 10.7 cm Flux
Observed 15 Aug 090
Predicted 16 Aug-18 Aug 095/095/095
90 Day Mean 15 Aug 096
V. Geomagnetic A Indices
Observed Afr/Ap 14 Aug 008/009
Estimated Afr/Ap 15 Aug 010/015
Predicted Afr/Ap 16 Aug-18 Aug 010/010-008/010-005/005
VI. Geomagnetic Activity Probabilities 16 Aug-18 Aug
A. Middle Latitudes
Active 25/20/15
Minor storm 10/10/05
Major-severe storm 01/01/01
B. High Latitudes
Active 30/30/15
Minor storm 15/15/05
Major-severe storm 01/01/01
Comment: Corrected flare probabilities.
