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000
FXUS64 KOHX 172239
AFDOHX

Area Forecast Discussion
National Weather Service Nashville TN
539 PM CDT Thu Aug 17 2017

.UPDATE...
FOR 00Z AVIATION DISCUSSION.

&&

.DISCUSSION...

It was very warm and humid at mid afternoon. Temperatures were in
the mid to upper 80s under partly cloudy skies. Southwest winds
were a little more breezy than you might expect on an August day,
gusting to 20 mph in some spots. The wind was the result of
pressure gradient between a high pressure center along the gulf
coast and low pressure over Wisconsin.

A cold front trailed from the low pressure, down to the Ozark
region. This front will continue to move toward Mid Tn late this
afternoon and evening, with scattered showers and thunderstorms
developing ahead of it. Development was already occurring from
West Ky down across the Delta Region. Dynamics and instability
will be unimpressive, but there may be enough diurnal instability
to form a few strong storms with heavy downpours and gusty winds.
The main time frame for this potential is between 4 PM and 8 PM
for areas along and west of Interstate 65. The greatest coverage
of showers and weakening storms for areas east of I-65 will occur
between 7 PM and midnight.

The actual surface front will take its time moving through the
Mid State, so at least small pops will linger into Friday morning
for the east half. Drier, but not really cooler, air will build in
for Friday afternoon, and will continue through the weekend.

Models show the tail of an upper level trough swinging across the
area Saturday, and some increasing moisture on Sunday. These
features mean a rogue shower cannot be completely ruled out this
weekend, but no rain will be mentioned in the forecast with pops
less than 10 percent.

Monday, eclipse day, looks like a typical August day. It will be
hot and humid. The morning may begin with total sunshine, then as
afternoon arrives, we will likely see some diurnal cumulus clouds
form as patches of thin cirrus move overhead. The best news is
that pops look very low with a prevailing upper level ridge. The
updated forecast will show 20 pops across the south half and less
than 15 percent over the north. Overall, we are optimistic about
seeing the eclipse, but it will probably not be perfect, and
viewers may have to deal with some annoying patchy clouds.

Looking ahead, chances for showers and storms will increase
Tuesday into Wednesday with approach of another front. Models
differ with the speed of this front and how long rain chances will
linger into late week, but all models indicate a shot of cooler
than normal air late next week.

&&

.AVIATION...
00Z TAF DISCUSSION.

BNA/MQY/CKV/CSV...A broken line of showers, with perhaps an
embedded thunderstorm or two, is slowly making its way into Middle
Tennessee. A surface front remains situated a little further to
our west, and won`t push through until after 12Z. Look for
scattered showers during the early evening, with the activity
diminishing significantly after we lose the surface heating, and
only isolated cells expected overnight. Ceilings will drop to at
least MVFR after 06Z, with skies clearing out from west to east
with Friday morning fropa.

&&

.OHX WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$

DISCUSSION......13
AVIATION........08