Area Forecast Discussion
Issued by NWS Nashville, TN
FXUS64 KOHX 251740
Area Forecast Discussion
National Weather Service Nashville TN
1140 AM CST Sat Feb 25 2017
FOR 18Z AVIATION DISCUSSION.
(Today thru Mon)
Cold front has now pushed just east of our eastern most counties.
Current temps range from the mid 40s northwest to the mid 50s
Plateau. Difficult temp fcst for today as low temps will bottom out
around 6-8 am and will be much cooler than temps at the 4 am
issuance time. Will likely need to update a few times between 4 am
and 8 am to get the temp wording correct. But, at any rate, using 6
am as a reference, it looks as though temps at that time will range
from the upper 30s northwest to mid 40s southern Plateau. By 8 am,
temps should be rather uniform and in the 40 to 45 degree range.
The cloud fcst for today looks as though it will be partly cloudy
for the most part. Upper trough axis will traverse the area today
but middle TN appears to be to the south of the better ul dynamics.
pva only extends southward through the ky areas and then becomes
generally neutral across the vol state. Thus, will only include a
slight chance of showers Plateau early. With 850 mb temps of -5c to
-8c by this afternoon, not looking for much in the way of a warmup.
caa will continue to feed across the area today as w to nw winds of
10 to 15 mph continue.
Tonight, the sfc high will be located over ern TN with clear skies
in place. Overnight lows will therefore be quite cold and will
generally be in the lower to mid 20s. Since its still February, not
issuing any special freeze statements at this time.
Warmup to commence on Sunday with highs back up into the mid 50s,
compliments of the return southerly flow.
On Sunday night and into Monday, shower chances will return as a
weak sfc trough drops southeast across western TN. Low temps Sunday
night will be in the upper 30s to lower 40s so not expecting any
frozen precip. The upper pattern will continue to carry a southerly
component and as impulses pop up through Monday night, shower
chances will continue.
(Tue thru Fri)
An unsettled and unseasonal warm wx pattern will continue to be in
store for at least Tue thru Wed of next work week, with a
progression to a more seasonal wx pattern emerging as the second
half of next work week progresses. In taking a closer look, a
continuance of the southwesterly flow pattern that has provided the
mid state seasonably warm temps as of late is expected to become
more developed at least thru Thu, before an upper level trough
passage occurs, resulting in, along with a sfc frontal passage
during the day on Wed, high pressure influences from the Rockies
being able to build into our region, resulting in dry conditions
with a return to seasonal normal temps for late in the work week.
As we now take a closer look at Tue thru Wed time frame, look for
increasing instability and weak upper level disturbances passages in
flow aloft to result in sct to numerous light shwrs Tue into Tue
night with iso tstms also possible. Best overall moisture,
instability, and lift potential look to occur across the mid state
region as Wed progresses ahead of sfc frontal passage, with sct to
numerous moderate shwrs and sct tstms possible during the day, with
the potential of lingering post sfc frontal moisture resulting in
iso to sct light shwrs during the evening hrs as upper level trough
moves through the mid state region.
As for temps, temps will warm to 15 to 20 degrees above seasonal
normals on Tue, mainly around 70, mid to upper 60s Cumberland
Plateau Region. Lows Tue night will be 20 to 25 degrees warmer than
normal, mainly in the mid to upper 50s. With increasing atm moisture
and associated rainfall potential, highs on Wed will be only in the
mid 60s. Lows Wed night will be closer to seasonal normal values in
the mid to upper 30s, with highs on Thu near seasonal norms in the
low to mid 50s, around 50 Cumberland Plateau Region. Lows Thu night
will be around seasonal normal values in the lower 30s. Highs on Fri
will be around seasonal normal values in the lower to mid 50s.
18Z TAF DISCUSSION.
A surface high pressure area will move across the Mid-State
through tomorrow morning. An area of scattered to broken cold air
stratocumulus, with bases abv 3500 ft, will sweep across the area
this afternoon, then give way to mostly clear conditions. tonight.
Upper flow turns quickly zonal tonight and Sunday, allowing for
scattered high clouds to edge back into the area by 18z Sunday.
VFR conditions are expected throughout the forecast period.