Joint USAF/NOAA Report of Solar and Geophysical Activity 11 Aug 2002
:Product: Report of Solar-Geophysical Activity
:Issued: 2002 Aug 10 2210 UTC
# Prepared jointly by the U.S. Dept. of Commerce, NOAA,
#Space Environment Center and the U.S. Air Force.
#
:Product: Report of Solar-Geophysical Activity
:Issued: 2002 Aug 11 2210 UTC
# Prepared jointly by the U.S. Dept. of Commerce, NOAA,
#Space Environment Center and the U.S. Air Force.
#
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 223 Issued at 2200Z on 11 Aug 2002
IA. Analysis of Solar Active Regions and Activity from 10/2100Z
to 11/2100Z: Solar activity remained at low levels. The two largest
x-ray flares of the period were optically uncorrelated: A C9.5
flare at 11/1147 UTC, and a C7.9 flare at 11/1801 UTC. LASCO
imagery revealed no evident CME activity following the first event,
and was unavailable for the second event, however neither event was
accompanied by any significant CME-related radio emissions. A
19-degree filament disappearance occurred near N28W51 at about
11/0700, close to the western end of a long filament channel that
extends to the northeast limb. No CME was evident in available
LASCO imagery following this event. Regions 61 (N07W28), 66
(N13E42), and newly numbered 69 (S08E77) were all sources of lesser
C-class activity. Region 61 appears to be undergoing an accelerated
decay in size and complexity. New Region 69 appears large and
complex in white light, but its limb proximity prevents a detailed
magnetic analysis. Three other regions were also numbered: 70
(N05W05), 71 (N11E68), and 72 (N18W23). All appear relatively
simply structured at present. 10cm flux experienced a rapid rise
with the appearance of the new regions.
IB. Solar Activity Forecast: Solar activity is expected to be
predominantly low, but with a fair chance for isolated M-class
activity over the next three days, primarily due to new Region 69.
IIA. Geophysical Activity Summary 10/2100Z to 11/2100Z:
The geomagnetic field was quiet to active. A trend toward elevated
solar wind speed and sustained southward Bz appeared to persist for
most of the day, and may indicate the early influence of expected
high speed stream effects.
IIB. Geophysical Activity Forecast: The geomagnetic field is
expected to range from quiet to active conditions for the next three
days.
III. Event Probabilities 12 Aug-14 Aug
Class M 35/35/35
Class X 01/01/01
Proton 01/01/01
PCAF green
IV. Penticton 10.7 cm Flux
Observed 11 Aug 172
Predicted 12 Aug-14 Aug 175/180/185
90 Day Mean 11 Aug 164
V. Geomagnetic A Indices
Observed Afr/Ap 10 Aug 013/016
Estimated Afr/Ap 11 Aug 013/018
Predicted Afr/Ap 12 Aug-14 Aug 012/012-015/015-012/012
VI. Geomagnetic Activity Probabilities 12 Aug-14 Aug
A. Middle Latitudes
Active 25/30/25
Minor storm 10/10/10
Major-severe storm 01/01/01
B. High Latitudes
Active 30/35/30
Minor storm 10/10/10
Major-severe storm 01/01/01
