Special Weather Statement, NWS Nashville, TN

Area Forecast Discussion
National Weather Service Nashville TN
1214 PM CDT Mon Jul 29 2024

...New AVIATION...

.SHORT TERM...
(Rest of today through Thursday Night)
Issued at 1108 AM CDT Mon Jul 29 2024

Quite a bit of cloud cover out there at forecast time, but shower
activity is pretty sparse. A few showers are being seen east of I-65
but most are getting a break. This looks like it won't be the case
all day, however. Upstream showers and thunderstorms from a decaying
MCS over southern Illinois continue to trek this way and while
intensities have dropped off significantly over the last few hours,
outflows from these storms could provide focusing mechanisms for
afternoon showers and thunderstorms here in the mid-state.
Fortunately, forecast shear values are meager throughout the
afternoon. 20-25 kts of deep layer shear should mitigate any severe
threat. Can't rule out a wind gust of 40-50 mph with any stronger
storm that may develop, but the bigger issue will be heavy rain.
Quite a bit of rain was seen along and east of I-65 yesterday,
especially north of I-40. If these same areas experience prolonged
rainfall this afternoon, at least some localized flooding may become
an issue.

Over the next 24-36 hours, as northwest flow aloft continues, models
persist in developing 2-3 more of these MCS-type features to our
northwest. One late tonight and another tomorrow afternoon, at
least. The downside is the poor ability of models to depict the
eventual trajectory of these type of thunderstorm complexes. For
now, in both instances, the highest PoPs will be along and east of
I-24. Again, some flooding is possible in areas that continue to
see multiple rounds of storms/heavy rain.

Afternoon highs (and eventual Heat Index values) over the next few
days may also prove to be tricky. Current NBM numbers suggest mid to
upper 90s in the afternoon tomorrow through Friday. Cloud cover and
afternoon storms may stymie some of this heat, especially east of
I-65, with those who miss out on any rain getting the brunt of
the heat. Of note, I've had to tamp down NBM dew points slightly
tomorrow as they seem very aggressive, but this still puts much of
our western 2/3 into Heat Advisory territory tomorrow afternoon.
This could also be the case each of the next few afternoons, but
we'll take one at a time due to the PoP uncertainty.

&&

.LONG TERM...
(Friday through next Monday)
Issued at 1108 AM CDT Mon Jul 29 2024

By Friday, we should start to lose the northwest flow aloft and
ridging to our west. This should slow down rain chances and allow
afternoon highs to moderate slightly. Extended guidance suggests
highs back into the low to mid 90s by the weekend and much lower
rain chances, but we'll have to see how an upper low to our north
pans out for the weekend. There could be enough influence for
Saturday afternoon storms and then a longer drying out period into
the start of next week.

&&

.AVIATION...
(18Z TAFS)
Issued at 1208 PM CDT Mon Jul 29 2024

Coverage of showers and thunderstorms has increased enough to
include VCTS and tempo groups in the 18Z tafs. Lower vsby in heavy
downpours and wind gusts to 30KT will be the main impacts. Outside
the storms, VFR conditions are expected this afternoon. Showers
and storms will diminish this evening. Later in the night, an MCS
will make a run at the area with impacts expected mainly at SRB/CSV.
Downpours and gusty winds are expected.

&&

.PRELIMINARY POINT TEMPS/POPS...
Nashville      77  97  79  99 /  40  30  30  20
Clarksville    77  96  77  96 /  40  20  20  10
Crossville     68  88  71  90 /  50  60  50  40
Columbia       75  97  76  97 /  20  20  10  10
Cookeville     71  90  73  91 /  50  50  50  30
Jamestown      69  87  72  91 /  60  60  70  40
Lawrenceburg   74  95  75  95 /  20  30  10  20
Murfreesboro   74  97  76  97 /  40  30  30  20
Waverly        75  97  76  97 /  30  10  10  10

&&

.OHX WATCHES/WARNINGS/ADVISORIES...
Heat Advisory from noon to 7 PM CDT Tuesday for Bedford-Cheatham-
Davidson-Dickson-Giles-Hickman-Houston-Humphreys-Lawrence-Lewis-
Macon-Marshall-Maury-Montgomery-Perry-Robertson-Rutherford-Smith-
Stewart-Sumner-Trousdale-Wayne-Williamson-Wilson.

&&

SHORT TERM...Unger
LONG TERM....Unger
AVIATION.....13

Special Weather Statement
National Weather Service Nashville TN
113 PM CDT Mon Jul 29 2024

TNZ008-009-029-291900-
Trousdale TN-Sumner TN-Macon TN-
113 PM CDT Mon Jul 29 2024

...A STRONG THUNDERSTORM WILL IMPACT SOUTHEASTERN SUMNER...WESTERN
MACON AND TROUSDALE COUNTIES THROUGH 200 PM CDT...

At 113 PM CDT, Doppler radar was tracking a strong thunderstorm 7
miles east of Gallatin, moving east at 25 mph.

HAZARD...Wind gusts up to 40 mph.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around
         unsecured objects.

Locations impacted include...
Gallatin, Hartsville, Westmoreland, Bledsoe Creek State Park, and
Bethpage.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

&&

LAT...LON 3638 8604 3634 8609 3633 8620 3634 8621
      3634 8622 3635 8623 3633 8625 3633 8627
      3634 8627 3635 8628 3632 8630 3632 8632
      3647 8644 3664 8613 3664 8611
TIME...MOT...LOC 1813Z 252DEG 23KT 3642 8633

MAX HAIL SIZE...0.00 IN
MAX WIND GUST...40 MPH

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Special Weather Statement
National Weather Service Nashville TN
121 PM CDT Mon Jul 29 2024

TNZ026-027-059-291900-
Williamson TN-Davidson TN-Cheatham TN-
121 PM CDT Mon Jul 29 2024

...A STRONG THUNDERSTORM WILL IMPACT CENTRAL DAVIDSON...NORTH CENTRAL
WILLIAMSON AND SOUTHEASTERN CHEATHAM COUNTIES THROUGH 200 PM CDT...

At 120 PM CDT, Doppler radar was tracking a strong thunderstorm over
Bellevue, or 9 miles southwest of Nashville, moving east at 25 mph.

HAZARD...Wind gusts up to 40 mph.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around
         unsecured objects.

Locations impacted include...
Nashville, Madison, Brentwood, Goodlettsville, Forest Hills, Oak
Hill, Belle Meade, Pegram, Bellevue, Antioch, Berry Hill, and Bells
Bend.

This includes the following highways...
 Interstate 40 between mile markers 193 and 215.
 Interstate 65 between mile markers 73 and 93.
 Interstate 24 between mile markers 41 and 58.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

&&

LAT...LON 3599 8699 3616 8706 3631 8672 3602 8666
TIME...MOT...LOC 1820Z 252DEG 23KT 3610 8694

MAX HAIL SIZE...0.00 IN
MAX WIND GUST...40 MPH

21