Area Forecast Discussion
Issued by NWS Nashville, TN
FXUS64 KOHX 252059
Area Forecast Discussion
National Weather Service Nashville TN
259 PM CST Sat Feb 25 2017
Conditions are much different than 24 hours ago across Middle
Tennessee. A cool air mass has settled into the region keeping us
a few degrees below our normal high temperatures. The northwest
breeze will relax this evening and overnight as the sfc high
currently centered over south central Oklahoma slides east. With
clear skies and calm winds, maximum radiational cooling will be
allowed. This means some of those overly ambitious plants that
have decided to bloom will be in for a little shock with lows
mainly in the low to mid 20s.
The sfc high will be east of the area on Sunday and southerly
winds will resume. Meanwhile aloft, zonal flow will begin to
shift to southwesterly flow ahead of the next disturbance. A
shortwave will move out of the southern plains Sunday night. Rain
will approach the western part of the area after midnight. Monday
afternoon will likely be drier than the morning west of I-65 as
the shortwave axis will be east of I-65.
Another ripple in the southwesterly flow will approach Monday
night into Tuesday leading to another chance of showers. Continual
southerly low level flow will allow enough moisture to become
established by Tuesday for enough instability to mention thunderstorms
during the day on Tuesday and overnight.
We could see a round of strong to severe thunderstorms on
Wednesday. GFS and Euro have come into agreement with the timing
of the system. A more amplified trough will swing across the
central plains. The associated sfc low will drag a cold front
through our area during the day on Wednesday. Ahead of the front,
temperatures will reach around 70 with dew points in the upper
50s. Along with respectable instability, there will be ample bulk
shear for organized updrafts. Unidirectional hodographs, storm
motions parallel to the front, and a 50-60 kt LLJ suggest a
straight line wind threat primarily. Decent mid level lapse rates
should be conducive for some hail as well.
After the cold front moves through Wednesday, high pressure will
slide into the area leading to a cooler and drier second half of
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.
.PRELIMINARY POINT TEMPS/POPS...
Nashville 27 55 42 59 52 / 0 0 30 60 50
Clarksville 24 54 41 58 51 / 0 0 60 60 40
Crossville 24 50 38 54 49 / 0 0 10 50 50
Columbia 26 55 41 58 52 / 0 0 30 70 50
Lawrenceburg 26 56 41 58 52 / 0 0 20 70 50
Waverly 25 54 41 59 53 / 0 0 60 60 50