639
FXUS64 KMRX 121145
AFDMRX

Area Forecast Discussion
National Weather Service Morristown TN
745 AM EDT Fri Jul 12 2024

...New AVIATION...

.SHORT TERM...
(Today and tonight)
Issued at 310 AM EDT Fri Jul 12 2024

Key Messages:

1. Hot and dry today, except for slight chance POPs in extreme
northeast TN mountain zones this afternoon.

Discussion:

Not much to discuss in the short term. Today will be hot and dry.
The only exception is across the extreme northeast TN mountain
zones, where slight chance POPs are in place for diurnal
convection. Highs will generally range from the low to mid 90s
across the area, which is around 5 degrees above normal. The only
near record temps for today will be in northeast TN. TRI has a
daily record high of 93 set back in 1993 and today`s forecast
high is 91.

Tonight, calm and clear with lows a few degrees above normal.

&&

.LONG TERM...
(Saturday through Thursday)
Issued at 310 AM EDT Fri Jul 12 2024

Key Messages:

1. Warming trend continues this weekend into early next week, with
the potential for record breaking daily high temperatures for the
start of the work week.

2. Outside of an isolated high elevation shower/storm, mostly dry
conditions are expected through Tuesday.

3. Widespread chances of precipitation return Wednesday and
Thursday.

Discussion:

By this weekend anomalous ridging and associated H85 temperatures
exceeding 30 degrees celsius will be in place across the Desert
Southwest and encroaching the southern fringes of the Pacific
Northwest. Locally, shortwave energy progressing to our north will
somewhat restrict upper level heights, moderating H85 temps closer
to near 20 degrees. This will continue to promote a warming trend
through the weekend with well above normal temperatures expected.
Additional height rises will combine with southwesterly low level
flow and favorable warm & moist air advection early next week to
bring potential record breaking daily high temperatures and the
possible need of heat related headlines. See the current daily
record high maximum temperatures and the latest forecast comparisons
below. Overall, Monday and Tuesday(15th and 16th) are trending to be
the warmest days of this expected heat wave.

Date   Chattanooga/Fcst  Knoxville/Fcst  Tri-Cities/Fcst  Oak Ridge/Fcst
07-14  103(1954)/100     101(1954)/97    98(1954)/93      101(1954)/97
07-15  103(1977)/102     98(1995)/100    96(1995)/96      100(1980)/100
07-16  105(1980)/101     100(1980)/99    100(1988)/96     103(1980)/99

Wednesday will remain hot, however, a more defined trough atop the
Great Lakes region and an associated frontal boundary draping south
towards the Tennessee valley will lead to increasing clouds and
chances for showers and storms. The cloud cover should help to
reduce ambient temperatures by a few degrees but increasing
dewpoints could still result in heat indices in the low 100s across
central and southern portions of the Tennessee valley.

Widespread chances of showers and storms will persist into Thursday
as the surface boundary slowly progresses through the forecast area,
hopefully bringing about some welcomed rainfall and cooler
conditions. Mean ensemble guidance suggest the probability of
rainfall greater than or equal to 0.50" through Wednesday through
Thursday night is 50-80% range, but the probability of 1.00" or
greater is only 30% or less.

&&

.AVIATION...
(12Z TAFS)
Issued at 713 AM EDT Fri Jul 12 2024

No change from previous discussion. VFR through the period with
light and northerly winds at CHA and TYS and VRB at TRI.

&&

.PRELIMINARY POINT TEMPS/POPS...
Chattanooga Airport, TN             97  73  98  75 /   0   0   0   0
Knoxville McGhee Tyson Airport, TN  95  71  96  72 /   0   0   0   0
Oak Ridge, TN                       94  70  96  71 /   0   0   0   0
Tri Cities Airport, TN              91  66  93  67 /  10  10  10   0

&&

.MRX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
TN...NONE.
VA...NONE.
&&

$$

SHORT TERM...
LONG TERM....KRS
AVIATION...