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Area forecast discussion 
National Weather Service Nashville Tennessee
1024 am CDT sun Aug 30 2015

Update...no major forecast changes are needed at this time. An
upper low was moving across Alabama toward Georgia...and a band of light showers
was pivoting across middle Tennessee...from Cookeville...to
Murfreesboro...Shelbyville and Pulaski. Short range models
continue to indicate the highest potential for showers and
isolated thunder along and east of Interstate 65 through the
day...then pulling off to the east tonight. More cloud cover
today will keep temperatures lower than yesterday...especially over our
southeast counties where temperatures will hold in the 70s.

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Previous discussion... /issued 624 am CDT sun Aug 30 2015/

Aviation update...for 12z taf's.

Bna/ckv/csv...sort of a mixed bag across middle Tennessee today
with likely probability of precipitation across the Cumberland Plateau, lesser chances
farther west. An upper low to our southeast continues to push
moisture into middle Tennessee while a weak surface front
approaches from the northwest. Will handle the lower probability of precipitation at bna and ckv
with vcsh remarks only, tempo showers around midday at csv. Expect
ceilings to remain VFR throughout. Look for some radiation fog
overnight at ckv and csv.

Previous discussion... /issued 317 am CDT sun Aug 30 2015/

Discussion...

It has been a fairly quiet night across middle Tennessee but today will
bring something to many who haven't seen it in quite awhile...
precipitation!

Clouds have been on the increase all night as moisture continues to
stream into the state due to a surface ridge positioned over the middle-
Atlantic Seaboard and the resultant boundary layer flow out of the
south. Aloft...a closed-low trough centered over the Gulf Coast
will pull to the northeast throughout the day. As it does...this
combination of low-level moisture and the passage of the upper
system will provide the middle-state with its best chances of rain we
have seen in awhile...and for the foreseeable future. Temperatures
will struggle today with this early onset of cloudiness. Many
south of I-40 and east of I-65 will struggle to get to 80 while
others...especially those west of I-65 will only reach the low
80s. This lack of heat will curtail any buildup of surface-based
instability...but with the passage the upper low...some thunder
will be possible by late morning and into the afternoon hours. No
severe weather is anticipated at this time...but it is August...so
one or two of these storms could become strong this afternoon. For
now...will bumps probability of precipitation a bit...remove the thunder wording from the
zones until 10 am or so and maintain it through early this
evening.

As the upper low pulls away from middle Tennessee and is replaced by weak
ridging aloft...a very stagnant pattern will develop across the
area. A very typical late-August air mass will settle in with
temperatures right around normal and dew points just high enough to
warrant an isolated shower or thunderstorm each afternoon throughout
the week. No one day has a better shot than the next and it could
be next weekend before any significant chances of rain returns to
middle Tennessee...though extended range guidance isn't even in
agreement about that.

Unger

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Ohx watches/warnings/advisories...none.

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