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000 
FXUS64 KOHX 211111
AFDOHX

Area Forecast Discussion
National Weather Service Nashville TN
511 AM CST Thu Nov 21 2019

.UPDATE...
FOR 12Z AVIATION DISCUSSION.

&&

.DISCUSSION...

This morning will start out much warmer than yesterday. South 
winds and increasing high clouds have kept temperatures in the 
40s overnight. For today, clouds will gradually lower and thicken 
as a cold front approaches from the northwest. A few showers will 
begin to develop this morning in our northwest counties and a few
light showers may spread across the rest of the Mid State in the  
afternoon. Most locations will stay dry today. South winds will 
bring mild air with highs in the low to mid 60s. 

The incoming front will stall across the Tn Valley tonight 
through early Saturday morning as a couple of low pressure waves 
move along the boundary. This will bring a soaking rain event with
1 to 2 inches of rainfall for most locations and some localized 
amounts in the 2 to 3 inch range across our southern counties. The
first wave will focus rain mainly along and north of I-40 late 
tonight into Friday morning. The second stronger wave with a
pronounced surface low will be focused mostly over the southeast 
half of our area Friday night into Saturday morning. A 45KT LLJ 
will bring a surge of deep moisture with PW values around 1.5 
inch. Some brief heavy downpours are possible, especially late 
Friday night when modest instability may create some rumbles of 
thunder. Brief, localized street flooding is possible, but we do 
not expect widespread flooding problems.

Most of the rain will move off to the east by midday Saturday as
the surface low gets kicked out by an approaching mid level
trough. But, low clouds and sprinkles are likely to remain through
Saturday night as low level moisture persists under the slow 
moving trough.

By Sunday, the mid level trough will be just to our east, with 
cooler air settling in. Some cloud cover will still be hanging 
around, especially across the Upper Cumberland where a few 
sprinkles may linger in the morning.

Conditions look quiet for the rest of Sunday through Monday, but
it looks like an active pattern will develop as we go into the
very busy travel period around Thanksgiving. A very breezy 
frontal system is expected to bring scattered showers Tuesday. 
This fast moving system should move out by early Wednesday, but 
models show more showers spreading across the region Thanksgiving 
Day into Friday. Post Thanksgiving travelers and shoppers could 
deal with very showery and unsettled conditions through the 
weekend across Middle Tn and surrounding regions. Good news is no 
wintry wx around here- that potential appears to be up across the 
Upper Midwest and Great lakes regions. 

&&

.AVIATION...
12Z TAF DISCUSSION.

While winds will pick up a little by 15Z for all terminals
(10-15 kts), VFR conditions are expected to remain until after
06Z/22 Nov. When they start to fall, look for MVFR to IFR
conditions with some of the heavier rains, especially near the end
of this TAF cycle.

&&

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

&&

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