:Product: 20030716RSGA.txt
:Issued: 2003 Jul 16 2200 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 197 Issued at 2200Z on 16 Jul 2003
IA.  Analysis of Solar Active Regions and Activity from  15/2100Z
to 16/2100Z:  Solar activity was low. Today's activity consisted of
three, low-level C-class flares from Region 410 (S12E28). This group
showed emerging flux and has developed some magnetic complexity.
However, the field intensity and sunspot area are still relatively
small. Region 409 (N16E27) continues to be the largest group on the
disk but showed overall decay and some simplification. Region 409
was quiet and stable during the past 24 hours. Two new regions were
assigned today: Region 412 (N16E19) and Region 413 (N18E49).
IB.  Solar Activity Forecast:  Solar activity is expected to be
predominantly low. There continues to be a chance, however, for an
isolated M-class event over the next three days. Region 409 is the
most likely source for energetic flares, but Region 410 might also
produce an M-flare if the current growth trend continues.
IIA.  Geophysical Activity Summary 15/2100Z to 16/2100Z:
The geomagnetic field ranged from active to major storm levels. An
initially active field attained storm levels after 0300 UTC and
continued at storm levels through 1500 UTC. Conditions returned to
active levels from 1500 UTC through the end of the period. The
increase in activity was associated with a slight increase in solar
wind speed (600 to 650 km/s) and a noticeable increase in total
magnetic field in the solar wind (ranging from 10 to 15 nT). The
solar wind signatures are consistent for the most part with a high
speed solar wind stream originating from a favorably positioned
coronal hole.
IIB.  Geophysical Activity Forecast:  The geomagnetic field is
expected to be mostly active with minor storm periods during the
next 24 hours as the current disturbance persists. A decrease to
unsettled to active is expected on the second and third days as the
high speed solar wind should gradually decline.
III.  Event Probabilities 17 Jul-19 Jul
Class M    35/35/35
Class X    05/05/05
Proton     05/05/05
PCAF       green
IV.  Penticton 10.7 cm Flux
Observed           16 Jul 133
Predicted   17 Jul-19 Jul  130/130/125
90 Day Mean        16 Jul 126
V.  Geomagnetic A Indices
Observed Afr/Ap 15 Jul  015/027
Estimated Afr/Ap 16 Jul  025/045
Predicted Afr/Ap 17 Jul-19 Jul  020/030-015/020-015/015
VI.  Geomagnetic Activity Probabilities 17 Jul-19 Jul
A.  Middle Latitudes
Active                40/30/30
Minor storm           30/25/25
Major-severe storm    10/05/05
B.  High Latitudes
Active                20/30/30
Minor storm           45/30/30
Major-severe storm    15/10/10