-- Discussion containing changed information from previous version are highlighted. --
911
FXUS64 KMRX 170530
AFDMRX

Area Forecast Discussion
National Weather Service Morristown TN
130 AM EDT Mon Jun 17 2024

...New AVIATION...

.UPDATE...
Issued at 918 PM EDT Sun Jun 16 2024

A few showers and thunderstorms will continue through the evening
hours sparking off of outflow from previous thunderstorms.
Coverage and intensity will continue to decrease now that the sun
has set. Have extended PoP chances a few hours longer than
previously forecasted for this evening to account for the
lingering thunderstorms.

&&

.SHORT TERM...
(This evening through Monday)
Issued at 256 PM EDT Sun Jun 16 2024

Key Messages:

1. Storms from this afternoon dissipating quickly this evening.

2. Hot again Monday with another chance of afternoon and early
evening storms.

Discussion:

The upper high center is past us now, leaving us with a little less
suppression of afternoon storms.  Storms that develop this afternoon
should dissipate during the evening cooling, with another round
Monday afternoon.  Both days will have the best chances of storm in
the mountains, however, on Monday the upper flow will be more
favorable for bringing convection out into the valley, so there
should be better coverage of storms up the I-81 corridor as storms
from the southern Appalachians move quickly off the mountains
northwestward across the valley. Also, dewpoints will be higher
Monday up the I-81 corridor as the return flow continues.

The storms from this afternoon will tend to travel to the northeast
along the terrain, but outflow boundaries will cause subsequent
storms on the flanks of the previous cells that will allow for
chances of storms in the foothills and somewhat out into the valley
as well.  Also, storms are traveling very slowly so localize
flooding is possible, but once again things should fall apart this
evening.

Temperatures will be hot again Monday but still staying below
advisory levels.

&&

.LONG TERM...
(Monday night through next Sunday)
Issued at 256 PM EDT Sun Jun 16 2024

Key Messages:

1. Hot weather to continue.

2. Low (20 to 30%) chances for thunderstorms to return for the
weekend.

Discussion:

The upper ridge that we will be talking about no matter how tired we
are of talking about it starts out due east of us on Tuesday before
beginning its vacation stay in the Mid Atlantic on Wednesday. With
our region on the edge of the highest heights of the anomalous
ridge, we will continue to run a few degrees above average but
should stay below our daily record highs. Ridge strength will peak
in intensity around 600 dm near NJ and NY by Thursday afternoon.
Locally here 700 mb heights will be near seasonal records on both
Wednesday and Thursday, which should help to stymie any convection
chances, especially with no other synoptic support to counterbalance
the ridge.

By Friday we might start to see some relief, ensembles have yet to
get on board, but both GFS and Euro deterministic guidance have
persisted in showing a weak tropical or subtropical low moving
underneath the ridge and coming ashore in the southeast on Thursday.
The path of the low thereafter is uncertain, but if it comes up our
way hopefully we can at least get clouds to stifle the heat. The
ridge position will be a little further south at this point, so the
existence of this low will be crucial to how pleasant or unpleasant
the start of the weekend shall be. To get a sense of spread, the
ensembles and NBM depict 93F in Chattanooga on Friday for a high,
GFS a little quicker with the low gets to 87F, and the Euro sits at
a cool 71F. In this case we have no choice but to wait and see and
stick close to the NBM and ensemble consensus, and meanwhile hope
the deterministic are right in their potential solutions. Should
the relief from the east not come to fruition, heat will persist a
bit longer before a potential break from a western trough arrives
beyond this period.

&&

.AVIATION...
-- Changed Discussion --
(06Z TAFS)
Issued at 128 AM EDT Mon Jun 17 2024

VFR conditions forecast to prevail through the period with Prob30
TSRA chances at TYS and TRI this afternoon. Patchy fog will be
possible early this morning, but confidence in terminal impacts
is too low to include in the TAF.
-- End Changed Discussion --

&&

.PRELIMINARY POINT TEMPS/POPS...
-- Changed Discussion --
Chattanooga Airport, TN             94  74  91  72 /  10  10   0   0
Knoxville McGhee Tyson Airport, TN  92  71  92  68 /  40  10   0   0
Oak Ridge, TN                       92  70  91  68 /  30  10   0   0
Tri Cities Airport, TN              88  68  89  64 /  70  20   0   0
-- End Changed Discussion --

&&

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

$$

SHORT TERM...
LONG TERM....Wellington
AVIATION...JB