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Tropical Storm HARVEY


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Tropical Storm Harvey Discussion Number  37
NWS National Hurricane Center Miami FL       AL092017
1000 AM CDT Tue Aug 29 2017

Heavy rains continue to spread over the Houston area and other
locations in southeastern Texas and southern Louisiana, exacerbating
what is already a catastrophic flood event.  Rainfall totals of
nearly 50 inches have been observed at several locations in the
Greater Houston area and southeastern Texas.  Storm totals
could reach higher amounts in some locations, which would be
historic for the area.

Harvey consists of a vigorous circulation of low clouds with some
patches of deep convection well to the north of the center and a
cyclonically curved convective band in the eastern semicircle. The
initial intensity is kept at 40 kt until we have a more recent
estimate when the reconnaissance plane checks the area this
afternoon.  Strong shear prevails over the cyclone, so no
significant change in intensity is anticipated before landfall. A
gradual weakening is forecast once the circulation moves inland.

The circulation is moving toward the north-northeast or 025 degrees
at 4 kt. Harvey is expected to be steered to the northeast with an
increase in forward speed by the mid-latitude southwesterly
flow ahead of a trough. Most of the guidance is consistent with this
solution, and the NHC forecast is in the middle of the guidance
envelope. Given that the guidance is tightly clustered the
confidence in the track forecast is high.

Key Messages:

1. Ongoing catastrophic and life-threatening flooding will continue
across southeastern Texas.  Additional rainfall accumulations of 6
to 12 inches are expected across the upper Texas coast into
southwestern Louisiana, with isolated storm totals as high as 50
inches.  Please heed the advice of local officials.  Do not attempt
to travel if you are in a safe place, and do not drive into flooded
roadways.  Refer to products from your local National Weather
Service office and the NOAA Weather Prediction Center for more
information on the flooding hazard.  A summary of rainfall totals
compiled by the Weather Prediction Center can be found at:
www.wpc.ncep.noaa.gov/discussions/nfdscc1.html

2. The flood threat has spread farther east into Louisiana.
Additional rainfall amounts of 5 to 10 inches are expected in
southern Louisiana into coastal Mississippi and Alabama.  Please
heed the advice of local officials and refer to products from your
local National Weather Service office and the NOAA Weather
Prediction Center for more information on the flooding hazard in
these areas.


FORECAST POSITIONS AND MAX WINDS

INIT  29/1500Z 28.4N  94.3W   40 KT  45 MPH
 12H  30/0000Z 28.8N  94.0W   40 KT  45 MPH
 24H  30/1200Z 29.8N  93.4W   40 KT  45 MPH...INLAND
 36H  31/0000Z 30.8N  92.8W   30 KT  35 MPH...INLAND
 48H  31/1200Z 32.0N  92.0W   30 KT  35 MPH...INLAND
 72H  01/1200Z 34.5N  89.5W   25 KT  30 MPH...POST-TROP/INLAND
 96H  02/1200Z 36.5N  86.0W   25 KT  30 MPH...POST-TROP/INLAND
120H  03/1200Z 38.5N  81.0W   20 KT  25 MPH...POST-TROP/INLAND

$$
Forecaster Avila

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