699
FXUS64 KMRX 241847
AFDMRX

Area Forecast Discussion
National Weather Service Morristown TN
247 PM EDT Mon Jun 24 2024

...New SHORT TERM, LONG TERM...

.SHORT TERM...
(This evening through Tuesday)
Issued at 218 PM EDT Mon Jun 24 2024

Key Messages:

1. Dry and hot conditions return for Tuesday.

Discussion:

An upper and surface ridging will build back into the Tennessee
valley and southern Appalachians. NAEFS shows PWS dropping to
around 2 deviations below normal with values of 0.6 to 0.8. These
values are also near the lowest 10 percentile. Definitely depicts
how dry the airmass will be for Tuesday morning.

The dry airmass will for large diurnal range of temperatures per
NBM guidance.

Overall, dry, mostly clear, and continued hot afternoon
conditions.

&&

.LONG TERM...
(Tuesday night through next Monday)
Issued at 218 PM EDT Mon Jun 24 2024

Key Messages:

1. Rain chances arrive on Wednesday into Thursday with a weak
frontal passage. Another front may bring showers and storms by the
weekend.

2. Above normal temperatures continue through the period with
slightly cooler temperatures expected Thursday before heating right
back up again Friday through Sunday.

Discussion:

Between the Bermuda High and the Four Corners High will be a 500 MB
trough that will encourage instability and a surface boundary for
Wed-Thur timeframe, aiding convective development.

The Four Corners High with will then stretch eastward, resuming a
drier weather pattern for late week, with precip limited mainly to
diurnal high terrain convection. But over the weekend, the high
pressure ridge will shift back westward again, opening another
northwesterly corridor for the impacts of another weather system
with a broad Saturday-to-Monday window of increased precip chances,
but peaking on Sunday. Given the heat during the period, tstms
should dot the convective areas during the extended period.

Speaking of heat, NBM dewpoints are progged to increase during the
Fri-Sun period, and GFS MOS supports that. Although I hedged the
dewpoints downward a bit this far out, afternoon heat indices during
Fri-Sun may top off between 100-105 degrees in portions of the
southern TN Valley, while running around 98-100 degrees in portions
of the northern Valley.

&&

.AVIATION...
(18Z TAFS)
Issued at 120 PM EDT Mon Jun 24 2024

VFR conditions throughout the forecast. Upper and surface ridging
building into the Tennessee valley.

&&

.PRELIMINARY POINT TEMPS/POPS...
Chattanooga Airport, TN             67  96  72  98 /   0   0   0  20
Knoxville McGhee Tyson Airport, TN  63  92  69  95 /   0   0   0  20
Oak Ridge, TN                       63  92  69  95 /   0   0   0  30
Tri Cities Airport, TN              58  90  65  92 /   0   0   0  30

&&

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

$$

SHORT TERM...DH
AVIATION...DH