:Product: 0819RSGA.txt
:Issued: 2006 Aug 19 2203 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 231 Issued at 2200Z on 19 Aug 2006
IA.  Analysis of Solar Active Regions and Activity from  18/2100Z
to 19/2100Z:  Solar activity was low.  Region 903, a plage region on
the west limb, produced a C3.8 flare at 19/1124Z.  Region 904
(S14W54) has shown little activity, producing only B-class flares.
IB.  Solar Activity Forecast:  Solar activity is expected to be very
low to low, with a slight chance for an isolated M-class flare from
Region 904.
IIA.  Geophysical Activity Summary 18/2100Z to 19/2100Z:
The geomagnetic field has been at quiet to major storm levels.  At
approximately 19/1100Z a small shock was observed at ACE.  The total
IMF strength increased to about 20 nT while the Bz component turned
southward and reached -15 nT.  The solar wind speed also increased
from about 400 km/s to about 450 km/s.  This resulted in two periods
of major storm levels at high latitudes from 1200 - 1800Z.  At time
of issue Bz remained southward at approximately -10 nT and solar
wind speed had decreased to about 400 km/s.  Today's shock arrival
is likely due to the full halo CME observed on 16 August.
IIB.  Geophysical Activity Forecast:  The geomagnetic field is
expected to be unsettled to active with a chance for isolated minor
storm periods on 20 August due to an expected coronal hole high
speed stream.  Quiet to unsettled conditions are expected on 21 - 22
August.
III.  Event Probabilities 20 Aug-22 Aug
Class M    10/10/10
Class X    01/01/01
Proton     01/01/01
PCAF       green
IV.  Penticton 10.7 cm Flux
Observed           19 Aug 089
Predicted   20 Aug-22 Aug  090/090/090
90 Day Mean        19 Aug 077
V.  Geomagnetic A Indices
Observed Afr/Ap 18 Aug  009/012
Estimated Afr/Ap 19 Aug  020/035
Predicted Afr/Ap 20 Aug-22 Aug  015/025-008/010-005/008
VI.  Geomagnetic Activity Probabilities 20 Aug-22 Aug
A.  Middle Latitudes
Active                30/20/15
Minor storm           15/10/05
Major-severe storm    05/01/01
B.  High Latitudes
Active                35/25/20
Minor storm           20/10/10
Major-severe storm    10/01/01