-- Discussion containing changed information from previous version are highlighted. --
743
FXUS64 KOHX 251120
AFDOHX

Area Forecast Discussion
National Weather Service Nashville TN
620 AM CDT Tue Jun 25 2024

...New AVIATION...

.SHORT TERM...
(Today through Wednesday)
Issued at 159 AM CDT Tue Jun 25 2024

Clear skies with temperatures ranging mid 60s to mid 70s
prevailing across mid state region just after top of the hour.
Dry conditions will continue to prevail through evening hours
tonight. Surface high pressure influences will continue shifting
eastward, with upper level ridging influences building across our
area. This will result in high temperatures by afternoon hours
today to be in mid to upper 90s across most locations west of
Cumberland Plateau Region, upper 80s to lower 90s for locations
just west of and across Cumberland Plateau Region. With more of
a southerly low level atmospheric flow regime, increased afternoon
humidity level expected, with locations approaching TN River
Valley Region with afternoon heat index values up to around 105
degrees. Not enough confidence presently to believe enough of this
area will be equal to or greater than 105 degrees to warrant
issuance of heat advisory product, but if temperatures/dewpoint
values go higher than currently forecasted, that could quickly
change. Will defer to the day crew and their interpretation of
latest temperature/dewpoint trends as morning into afternoon hours
progress for potential issuance of a heat advisory product.

As upper level ridging influences begin to break down as tonight
progresses, and an upper level shortwave approaches western
portions of mid state region late, shower and thunderstorm chances
will increase from west to east as day progresses, with best
chance of showers and thunderstorms during the Wednesday
afternoon hours. Most favorable CAMs model sounding profiles and
derived indices for potential of a few strong to pulse severe
thunderstorm development show MU CAPE values around 3,000 J/KG,
around 6.5 C/KM low to mid level lapse rates, Total Totals in
lower 50s, PW values approaching 1.75 inches, LI`s around -9, but
not a lot of atmospheric shear of note. Latest SPC Day 2 Outlook
continues to keep mid state under a marginal risk of severe
thunderstorms. Lows tonight will continue the muggy trend of late
ranging in low to mid 70s, upper 60s to around 70 for locations
just west of and across Cumberland Plateau Region. Highs on
Wednesday will be dependent on actual shower/thunderstorm
coverage, but most areas will experience highs in low to mid 90s.

&&

.LONG TERM...
(Wednesday Night through next Monday)
Issued at 159 AM CDT Tue Jun 25 2024

Best chances of showers and thunderstorms will be across eastern
portions of mid state region Wednesday night as upper level
troughing influences move over this area with a north to south cold
frontal passage expected also. Temperatures will back down to near
seasonal values for Wednesday night into Thursday with isolated to
scattered shower and thunderstorm chances mainly confined to
eastern and southern portions of our area. Other than some
isolated showers and thunderstorms being possible across highest
elevations of Cumberland Plateau Region on Friday afternoon due to
orographic lifting mechanisms, dry conditions will prevail across
our area Thursday night through Friday Night. Surface high
pressure influences centered across Great Lakes Region shortly
after sunrise on Thursday morning with shift into New England
area as this period progresses, with initial quasi ridging
influences aloft being replaced by a more progressive
southwesterly flow aloft pattern as Saturday progresses. Most of
eastern CONUS will be in warm sector of developing synoptic
surface frontal system ushering in once again low level
atmospheric southerly flow with high temperatures once again in
mid to upper 90s west of Cumberland Plateau Region. This weather
pattern will be supportive of isolated to scattered showers and
thunderstorms over the weekend, and depending on actual coverage,
it looks like most locations west of Cumberland Plateau Region
will have heat index values within heat advisory ranges by
Saturday afternoon and possible again on Sunday afternoon. Another
surface frontal passage will occur as day progresses on Sunday,
leading to influences of surface high pressure influences to our
north providing slightly cooler temperatures, but still continuing
seasonably warm, with isolated to scattered showers and
thunderstorms once again possible during afternoon hours on
Monday.

&&

.AVIATION...
-- Changed Discussion --
(12Z TAFS)
Issued at 618 AM CDT Tue Jun 25 2024

Light and variable winds will become south-southwesterly this
morning, then most likely light and variable again tonight. No VIS
restrictions anticipated or clouds even. VFR all the way.
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&&

.PRELIMINARY POINT TEMPS/POPS...
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Nashville      98  74  95  72 /   0  10  60  60
Clarksville    96  74  91  69 /   0  10  70  40
Crossville     90  67  91  65 /   0   0  40  60
Columbia       97  71  97  70 /   0   0  60  60
Cookeville     92  70  91  68 /   0  10  40  60
Jamestown      91  69  91  67 /   0  10  40  60
Lawrenceburg   96  71  95  69 /   0   0  50  60
Murfreesboro   98  71  97  70 /   0   0  60  60
Waverly        97  73  92  69 /   0  10  70  50
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&&

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

$$

SHORT TERM...JB Wright
LONG TERM....JB Wright
AVIATION.....05