860 
FXUS64 KMRX 191852
AFDMRX

Area Forecast Discussion
National Weather Service Morristown TN
252 PM EDT Sun Jul 19 2026

...New DISCUSSION...

.KEY MESSAGES...
Updated at 246 PM EDT Sun Jul 19 2026

- Isolated to scattered showers and storms continue through this
  evening, and again on Monday afternoon. A few strong to
  marginally severe storms are possible during these times along
  with gusty winds and localized flooding.

- Possible strong cold frontal passage Tuesday into Wednesday bears 
watching for severe weather capability. 

- Below normal temperatures and drier air will follow beyond 
Wednesday.

&&

.DISCUSSION...
Issued at 246 PM EDT Sun Jul 19 2026

Isolated to scattered showers and storms are ongoing this afternoon. 
This activity will persist through this evening, decreasing in 
coverage after sunset with loss of heating. A few strong strong to
marginally severe storms are possible due to moderate CAPE, but
very weak bulk shear. The main threat with any stronger storm 
will be localized gusty winds. Heavy rain is also expected as 
PWATS are around 2 inches, this may lead to isolated flooding for 
some as hourly rain rates will be several inches per hour in some
cases. Any area that sees repeat heavy showers through this 
evening will be most at risk for flooding. Again, gusty wind 
threat and flood threat will be isolated.

Tomorrow, we are expecting another round of afternoon convection but 
it should be more isolated. Having said that, a few strong storms 
are once again possible and may produce gusty winds and flooding.
The best coverage of storms will likely be for areas east of 
I-75, and greatest across the east TN mountains and possibly
foothills.

Tuesday/Wednesday, we are still watching an upper trough and cold
front that may lead to strong to severe storms Tuesday night into
Wednesday morning. This is due to an expected increase in shear 
during this time. SPC currently has areas along and north of I-40 
in a Slight risk, with a marginal risk for areas south of I-40. We
are still not in range of the CAMS, but the longer range 
deterministic models and ensembles show convection arriving late 
Tuesday night/early Wednesday morning. According to the NAM 
soundings, the environment still looks supportive of strong storms
even during the overnight hours, which typically isn't the case. 
While strong and gusty winds and heavy rain/isolated flooding 
will be the main threats, a low end tornado threat will also exist
due to the shear in place. The tor threat will ultimately depend 
on whether storms remain surface-based during the overnight hours 
or become elevated. Joint LREF Probs for surface CAPE above 500 
J/kg and Bulk Shear greater than 30 kts during the overnight hours
ranges between 30 and 50% north of I-40.

Following the mid-week cold front, Thursday will be very nice with 
low to mid 80s highs and dew points in the 60s under high pressure. 
Temperatures rise a couple of degrees into the weekend, but for the 
most part remain below normal. A shortwave cycling the top of the 
upper ridge Friday into Saturday, may bring precipitation chances 
back to the area and unfortunately increased dew points yet again.

&&

.AVIATION...
(18Z TAFS)
Issued at 139 PM EDT Sun Jul 19 2026

Scattered showers and storms are expected this afternoon through
early evening. VCTS and prob30 are in for all sites during this 
time. MVFR conditions possible with any passing shower or storm 
directly over a terminal. Otherwise, VFR conditions expected. 
Lastly, fog is possible tomorrow morning for any site that 
receives enough rain through this afternoon and evening but not
confident enough to mention yet in TAFs.

&&

.PRELIMINARY POINT TEMPS/POPS...
Chattanooga Airport, TN             74  92  75  93 /  20  40  10  30 
Knoxville McGhee Tyson Airport, TN  72  90  74  90 /  30  20  10  30 
Oak Ridge, TN                       72  90  73  90 /  30  20  20  40 
Tri Cities Airport, TN              68  88  69  88 /  30  20  50  70 

&&

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

$$

DISCUSSION...99
AVIATION...99


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