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fxus64 kohx 232202 

Area forecast discussion
National Weather Service Nashville Tennessee
502 PM CDT Mon Oct 23 2017

for 00z aviation discussion.



Fall air has finally arrived, and it looks like a seasonably cool
pattern will continue through the forecast period, especially for
the weekend.

At mid afternoon, a cold front was over east Tennessee. Post frontal
clouds and a few light showers remained in place across much of
mid Tennessee. A clearing line was noted over our western counties.
Look for the scattered light showers to continue through the next
few hours, gradually pushing off to the east into the early
evening. The clearing line will advance eastward across most of
mid Tennessee this evening, but the partial clearing will be temporary,
with some additional patches of cloud cover expected later in the
night. The clouds coming in later will be associated with an upper
level disturbance and a reinforcing shot of cool air. No rain
chances will be included late tonight, but a few passing sprinkles
cannot be ruled out. Temperatures will slip into the 40s across
the area tonight. A west breeze will continue, mainly in the 5-10
mph range.

For Tuesday and Tuesday night, another upper level wave will help
dig out a sharp upper trough axis. The axis will extend from the
Great Lakes all the way south to the Gulf Coast. This impulse may
bring a few sprinkles or light showers Tuesday afternoon, mainly
west of I-65. Otherwise, the main effect will be more
reinforcement of cool air. Highs Tuesday will reach the mid 50s
to lower 60s, or 5-10 degrees below normal. Lows Tuesday night
will dip into the 30s, also 5-10 degrees below normal. The big
question will be frost potential. Right now, it looks like at
least patchy clouds and some wind will inhibit frost development,
but the potential is something to keep in mind, especially for low
lying areas.

On Wednesday, skies will be partly to mostly sunny, but it will be
cool with highs in the 50s. Wednesday night will again bring
potential for patchy frost. With clearing skies and lighter
winds, it appears the frost potential will be greater than Tuesday
night, especially across the upper Cumberland.

Thursday will bring a big warmup as heights build ahead of the
next upper trough digging into the plains. High temps will climb
into the 60s under mainly sunny skies.

Looking ahead to the weekend, another big trough will dig into the
region. The leading cold front will start to bring showers
Friday, and depending on the model, showers could linger well into
Saturday. The air will be the coldest so far, with strong
potential for frost and some areas of freezing temperatures early
next week. Some rumors are indicating a possible Snowflake on the
back side of the moisture. Although a stray flake cannot be
completely ruled out, the occurrence would be unlikely and


00z taf discussion.

Bna/mqy/ckv/csv...surface front has already cleared the mid state
with low ceilings and patchy drizzle on their way out. Occluded
front will pass over later this evening with the upper low passing
very close to the mid state tomorrow. So we can expect a few more
clouds tomorrow, but any ceilings will remain VFR. Fortunately,
winds will stay up enough overnight to keep fog from becoming
troublesome. With the exception of some MVFR ceilings early this
evening, look for VFR wx for at least the next 24 hrs.


Ohx watches/warnings/advisories...


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