Area Forecast Discussion Issued by NWS Nashville, TN
000
FXUS64 KOHX 010445
AFDOHX
Area Forecast Discussion
National Weather Service Nashville TN
1045 PM CST Thu Nov 30 2023
...New AVIATION...
.UPDATE...
Issued at 727 PM CST Thu Nov 30 2023
Regional radar imagery this evening shows rain spreading into West
Tennessee with some radar echoes showing up aloft in our
southwest counties. 00Z OHX sounding indicates the lower
atmosphere remains very dry across Middle Tennessee, so it will
take until closer to or after midnight before rain can saturate
the low levels and reach the surface in our area. After midnight,
rain will spread across the entire cwa with pops rising to near
100 percent, before decreasing from west to east Friday morning.
Rainfall totals are still anticipated to be around one half inch
or less before the first round of rain ends Friday morning.
As far as temperatures, they remain in the upper 40s and 50s this
hour due to the ongoing WAA. However, dewpoints are still in the
20s, so as rain falls into the dry surface layer overnight,
temps will quickly wet-bulb down into the 40s and hover there.
Finally, surface winds have decreased this evening after being
gusty during the day today, but winds will ramp up again overnight
as the core of a 60+ kt 850mb jet moves overhead. A very strong
low level temperature inversion and widespread rain will keep the
strongest winds from mixing down to the surface, but still
anticipating some gusts of 30 to 35 mph at times towards sunrise.
Forecast has all of this covered well and only made some minor
tweaks.
&&
.SHORT TERM...
(This afternoon through Friday Night)
Issued at 246 PM CST Thu Nov 30 2023
High pressure continues to push east out of our area and we are
starting to see mid to high level clouds build in ahead of an
approaching trough. Winds this afternoon are gusting up to 25 mph
and a dry air mass remains in place with afternoon humidity in
the 20 percent range. These winds and low humidity are binging
elevated fire weather conditions this afternoon. Winds will let up
this evening and we will see humidity increase as the upper level
trough starts to lift out of TX.
Our quiet weather tonight will be replaced by breezy conditions
along with rain. As the trough lifts we will see a low level jet
increase becoming 50-70 knots at 850 mb. There is a strong
inversion and for the most part these strong winds will stay aloft
but given the pressure gradient we will see breezy winds
overnight into tomorrow morning, wind gusts 30-35 mph can be
expected and if rain mixes down any of the stronger winds we could
see isolated gusts up to 40 mph. The strengthening low level jet
will bring increased warm air advection and widespread rain to the
area. Rain will push in from west to east mainly after midnight.
Thunderstorm chances look to remain very low but there is some
elevated instability above the inversion and few lightning strikes
can`t be ruled out but overall unlikely.
Widespread rain will be tapering off during the morning with some
showers lingering into the afternoon. Rain totals are overall
looking light over the area with the better dynamics and QPF
staying to our north and west. Rain totals for our area through
Friday morning are looking to be 0.35-0.65" in the northwest
tapering off to less than 0.25" in the southeast.
&&
.LONG TERM...
(Saturday through next Thursday)
Issued at 246 PM CST Thu Nov 30 2023
The forecast becomes a bit more uncertain as we head into
Saturday. As the trough pulls away it will put a boundary across
the region. Ahead of this boundary we will see good Gulf moisture
along with warm air advection. This will bring periods of light
to moderate rain. The uncertainty is on where we see this boundary
set up. The EC ensemble is further south and east with the trough
to our northwest placing this boundary mainly to the east of our
area, the GFS ensemble is further north and west placing the
boundary over Middle TN. Confidence in high on little rain in the
northwest Saturday but confidence in low on rain totals for the
eastern half of the area. Right now QPF is looking to be
0.40-0.90 in the southwest falling off to less than 0.10" as you
work northwest.
The long wave trough over the Great Lakes will start to push east
Sunday into Monday and that will push a cold front through our
area. This will keep showers in the forecast for Sunday with
things drying out for Monday. We will then be on the edge of long
wave troughing over the Northeast through the middle of the week.
The impacts will be small with things looking to remain dry.
&&
.AVIATION...
(06Z TAFS)
Issued at 1041 PM CST Thu Nov 30 2023
While all TAF sites are currently VFR, that will be changing over
the next few hours as SHRA continues to move through the area. Low
cigs will move in area wide by 14Z and remain below VFR through
at least 06Z. SHRA will begin to move out by the afternoon. S/SE
winds continue through the TAF period, becoming gusty (15 to 25
kts) overnight into the morning hours.
&&
.PRELIMINARY POINT TEMPS/POPS...
Nashville 45 66 55 63 / 100 80 50 60
Clarksville 44 65 49 60 / 100 70 30 40
Crossville 40 58 51 61 / 90 90 70 80
Columbia 44 65 56 64 / 90 80 60 70
Cookeville 44 61 54 62 / 100 90 60 70
Jamestown 41 59 52 62 / 90 90 60 70
Lawrenceburg 45 64 57 64 / 90 90 70 70
Murfreesboro 44 65 56 65 / 100 90 60 70
Waverly 42 65 49 60 / 100 70 30 30
&&
.OHX WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
UPDATE.......Shamburger
SHORT TERM...Mueller
LONG TERM....Mueller
AVIATION.....Adcock