094
FXUS64 KMRX 240629
AFDMRX

Area Forecast Discussion
National Weather Service Morristown TN
Issued by National Weather Service Nashville TN
229 AM EDT Tue Jun 24 2025

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

.SHORT TERM AND LONG TERM...
(Today through next Monday)
Issued at 229 AM EDT Tue Jun 24 2025

Key messages:

1. Hot temperatures continue through Wednesday. A slight reprieve
from the heat is expected thereafter, though still warm.

2. Isolated to scattered storms over the higher terrain outside of
the TN valley will each afternoon and evening through Friday.

3. Rain chances increase this weekend into early next week as the
pattern becomes more active.

Discussion: A strong upper ridge will be centered directly over
our forecast area and the southern Appalachians through Wednesday
before weakening significantly by week`s end as an active northern
stream jet impinges from the north and some sort of tropical wave
works westward across Florida`s great bend area. Though weakened,
we`ll keep broad ridging in place through the weekend before what
appears like a pattern change takes place next week with the
ridge flipping to the western CONUS and a trough developing in the
east.

In terms of impacts, the heat is the main forecast item of note
really. Today will be warm no doubt, but Tuesday and Wednesday will
be the warmest with widespread mid and upper 90s expected. Resulting
afternoon heat index values will push into the 103 to 108 degree
range for much of the TN valley. A heat advisory has been issued to
account for this. It seems unlikely the higher terrain of the
Cumberland Plateau, east TN mountains, and our western NC and
southwest VA counties will reach that 103-108 heat index range so
they were left out of the heat advisory for the time being. One
other caveat, I would be willing to bet the Sequatchie river valley
will see those heat index values but there`s also a significant
portion of those counties at elevation. For now we`ve got the most
populated areas accounted for so I will let future shifts further
refine the extent of the advisory.

Otherwise, rainfall through late this week will be hard to come by
but not non-existent. Today through Wednesday afternoon and evening
convection is expected over the mountains and plateau areas. Some of
this may push out into the lower elevations via outflow boundaries
but most areas should be dry. An increase in shower/thunderstorm
coverage is expected Thu and Fri as the ridge weakens. Then this
weekend into early next week could be fairly active as the ridge
further weakens and shortwave activity and resulting boundaries
approach the area from the north.

&&

.AVIATION...
(00Z TAFS)
Issued at 718 PM EDT Mon Jun 23 2025

VFR conditions at all TAF sites will continue. Surface ridging
into the Tennessee valley will keep winds light.

&&

.PRELIMINARY POINT TEMPS/POPS...
Chattanooga Airport, TN             97  74  98  74 /   0   0  10  20
Knoxville McGhee Tyson Airport, TN  97  74  97  73 /  10  10  20  20
Oak Ridge, TN                       97  74  97  72 /   0  10  20  20
Tri Cities Airport, TN              95  70  93  69 /  10  20  30  30

&&

.MRX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
TN...Heat Advisory from 1 PM EDT /noon CDT/ this afternoon to 7 PM
     EDT /6 PM CDT/ Wednesday for Anderson-Bledsoe-Bradley-
     Grainger-Hamblen-Hamilton-Hawkins-Jefferson-Knox-Loudon-
     Marion-McMinn-Meigs-North Sevier-Northwest Blount-Northwest
     Cocke-Northwest Greene-Northwest Monroe-Rhea-Roane-
     Sequatchie-Sullivan-Union-Washington TN-West Polk.

VA...NONE.
&&

$$

SHORT TERM/LONG TERM... DH/CD
AVIATION...DH