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000
FXUS64 KOHX 170527
AFDOHX

Area Forecast Discussion
National Weather Service Nashville TN
1227 AM CDT Wed Apr 17 2024

...New AVIATION...

.UPDATE...
Issued at 815 PM CDT Tue Apr 16 2024

Radar showing convection moving across western TN at this hour.
Latest sfc map indicates most of the rainfall that is reaching
the ground is back toward the TN river. We should continue to see
the rainfall spread eastward overnight. 850 mb showalter values
still expected to remain negative and thus, will keep thunder in
the forecast. Gridded pops appear to be on track. Otherwise, the
clouds and the southerly flow should keep min temps elevated
tonight. Still rather warm out presently with values holding, for
now, in the 70s. So, no changes to current forecast.

&&

.SHORT TERM...
(Rest of today through Wednesday)
Issued at 1020 AM CDT Tue Apr 16 2024

This morning`s showers have moved out of the CWA and satellite
imagery shows cloud cover diminishing as the boundary layer sees
better mixing. Temperatures are lagging behind by 2-3 degrees
from where they were at this time yesterday. There is a large
break in cloud cover that has developed W of I-65 and is expanding
E. This should allow for better heating leading to our highs
today still reaching the low to mid 80s. This evening, cloud cover
will increase once again ahead of a developing front associated
with a surface low over Nebraska. As this front marches E, shower
activity is expected to increase over Middle TN late tonight into
early Wednesday morning.

We have been monitoring the threat for severe weather on
Wednesday, and overall, the threat is looking minimal for Middle
TN at this time. Latest SPS outlook has shifted the slight risk N,
leaving TN with a marginal risk. There are a few issues with the
overall set up. One being the location of the surface low. The low
is currently over Nebraska and is forecasted to track NE into
Iowa and then Michigan. This keeps the best forcing N of TN.
Additionally, the front itself looks to bring very little moisture
into TN with some of the latest CAMs showing no precipitation at
all moving through. Taking a look at the 500mb level, there is
some diffluent flow Wednesday morning, but quickly becomes mostly
zonal by Wednesday afternoon/evening limiting upward motion. Some
pros, Wednesday afternoon, CAMs forecast sufficient CAPE values
around 1500-2000 J/kg, good mid-level lapse rates from 7-9 C/km,
and sufficient deep layer shear along with storm helicity values
between 150-290. That said, these things don`t matter if storms
don`t develop. This will ultimately be the question and something
that will have to be monitored through the day Wednesday. If
storms do develop, some could become severe with he greatest
threat being wind and hail at this time.

&&

.LONG TERM...
(Wednesday Night through next Tuesday)
Issued at 1020 AM CDT Tue Apr 16 2024

A brief break in the rain is expected Wednesday night and Thursday
morning, however, a large upper-level low setting up over southern
Canada and a series of embedded shortwaves will keep an active
pattern continuing through the weekend. Off-and-on showers with a
few thunderstorms will be possible each day Thursday through
Sunday, and temperatures will gradually cool through the weekend.
Can`t rule out a stray strong thunderstorm on Thursday, but CAPE
and shear values look too weak for a widespread severe threat. Dry
weather returns next Monday, but a look out into the extended
hints that it might not last that long.

&&

.AVIATION...
(06Z TAFS)
Issued at 1220 AM CDT Wed Apr 17 2024

As a weak front approaches, isolated to scattered showers will
impact the area through the morning. While the probability is
low, an isolated thunderstorm may also develop through about 18Z.
Ceilings will also fall with MVFR cigs possible between 12Z and
18Z. Otherwise, southerly to southwesterly winds will be gusty
with gusts of 15 to 25 knots at times before finally tapering off
after sunset Wednesday.

&&

.PRELIMINARY POINT TEMPS/POPS...
Nashville      82  64  86  62 /  50  10  30  90
Clarksville    83  62  85  58 /  20  20  40  90
Crossville     72  59  81  60 /  50  10  20  80
Columbia       80  63  86  61 /  60  10  40  90
Cookeville     74  62  82  61 /  60  20  20  90
Jamestown      75  59  82  59 /  60  20  20  80
Lawrenceburg   78  63  85  62 /  70  20  30  80
Murfreesboro   79  63  87  61 /  60  10  30  90
Waverly        83  63  86  57 /  20  10  40  90

&&

.OHX WATCHES/WARNINGS/ADVISORIES...
None.
&&

$$

UPDATE.......21
SHORT TERM...Cravens
LONG TERM....Reagan
AVIATION.....Clements