Forecast Discussions mentioning any of "ACARS" "MDCRS" "AIRCRAFT" "TAMDAR" "AMDAR" "WVSS" received at GSD on 01/26/21

Area Forecast Discussion

National Weather Service Nashville TN

 535 PM CST Mon Jan 25 2021

.UPDATE...
FOR 00Z AVIATION DISCUSSION.

&&

.DISCUSSION...

A line of heavy showers is currently moving across Middle
Tennessee mainly north of I-40. These showers earlier produced
some strong winds at the surface, but they have since diminished
somewhat. An ACARS sounding for BNA taken at 1709Z shows very
little CAPE with nearly total saturation from the surface up to
about 650 mb. There is some speed and directional shear in the
low-levels, but at this time helicities aren`t excessive. A warm
front that moved northward through Middle Tennessee overnight has
become quasi-stationary near the TN/KY border, so most of Middle
Tennessee is now in the warm, moist sector. A pre-frontal trough
will swing through the mid state later this afternoon and evening,
and this will provide some focus for the expected storms. The HRRR
does suggest some convective organization along this boundary, but
given the lack of instability in this air mass, it still appears
that the primary threats are going to be wind-related. SPC
currently gives us a 5% risk of damaging winds and a 2% risk of
tornadoes in the marginal/slight risk area, which covers nearly
all of Middle Tennessee. Even though the bulk of the active
weather will move across and exit the mid state overnight, the
cold front won`t actually arrive until Wednesday. That`s going to
be our next chance of rain, with perhaps some snow for the
Cumberland Plateau Wednesday night. (It`s going to be another
battle of cold air vs. moisture.) After that, look for cooler
temperatures the remainder of the week, with perhaps a weekend
cold front representing our next chance of rain.

&&

.AVIATION...
00Z TAF DISCUSSION.

Showers and occasional storms will impact BNA/MQY/CSV through the
evening which will reduce vis to IFR conditions periodically. A
surface front will move through the area from west to east which
will shut off rain chances by 07z. Cigs will gradually improve to
VFR for the remainder of the taf period by the morning. Behind
the surface front winds will shift to the WSW.

&&

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

&&

$$

DISCUSSION......08
AVIATION........Reagan