802 
FXUS64 KMRX 130624
AFDMRX

Area Forecast Discussion
National Weather Service Morristown TN
224 AM EDT Mon Jul 13 2026

...New DISCUSSION...

.KEY MESSAGES...
Updated at 223 AM EDT Mon Jul 13 2026

- Scattered showers and storms continue today, lessening tomorrow. A 
  Flood Watch remains in effect into this evening.

- Though chances are very low, cannot rule out a strong gusty wind 
  or two in any stronger thunderstorm.

- More typical summer weather Wednesday onwards with near normal
  temperatures and only a low PM chance of scattered
  thunderstorms.

&&

.DISCUSSION...
Issued at 223 AM EDT Mon Jul 13 2026

Most rain has either dissipated for the night or steadily 
weakened, though a few showers may linger or re- develop into the 
morning. Additional flooding early this morning is unlikely.

HREF/REFS guidance has been consistently depicting a LPMM (a type of 
probability matching mean) bulls-eye of heavy rainfall from 
Maryville down through Polk County later today into this evening. 
Now, CAMs have not been nailing locations well the last couple of 
days, so spatial uncertainty is still quite high. My concern though 
is with our increasingly saturated grounds and one more day of 
scattered to numerous convection, it makes more sense to keep the 
Flood Watch around for 1 more day and see how the storms play out. 
Rather have the watch out and cancel later on then to cancel now 
only to have additional issues tomorrow. A couple days ago it was 
Cocke and Greene counties that saw significant flooding, then 
Knoxville had a round of urban flooding a few hours ago, and 
meanwhile other counties have seen flooding to a lesser extent.

If the storms do set up over the southern counties, those counties 
have seen less rain the last few days than elsewhere. Contrast 
Monroe and McMinn counties to portions of Meigs, Loudon, on over to 
Blount and north. Flash flood guidance (aka the amount of rain 
needed in a certain amount of time to produce flash flooding) is 
quite low along the northern foothills and even Meigs (1 to 2 inches 
in 3 hours), but still quite high in Monroe and McMinn (2.5 to 3 
inches needed in 3 hours). So, depending on where storms set up will 
determine how quick flooding can occur. Ultimately in this 
environment if it rains hard enough long enough then even the drier 
counties will flood. Because of this I have opted to extend the 
Flood Watch into this evening and see how it all plays out.

The cutoff low responsible for our rainy misery the last couple of 
days won't cross the Mississippi River heading west until Wednesday. 
But at least tomorrow it will be a little further away, and thus its 
influence over East Tennessee will be increasingly lesser. Still 
likely won't be an entirely dry day, but any flood impacts would be 
incredibly isolated, if they occur at all. I would expect the bulk 
of the coverage to be south of Knoxville, and ideally any storms 
that do form north will have better storm motions.

As we progress through the week upper heights build slightly and 
between that and the departure of the closed low and associated 
widespread cloud cover, we'll see temperatures tick back upwards a 
tad. Not a heat wave, but it'll certainly get us back into the 
regular hot and muggy period for this time of year. Since we're 
maintaining a fairly moist airmass, there'll be daily storm chances, 
primarily in the afternoon and early evening hours, as is fairly 
typical for summer.

&&

.AVIATION...
(06Z TAFS)
Issued at 1144 PM EDT Sun Jul 12 2026

Will see a mix of mainly VFR/MVFR overnight into Monday with 
showers around especially TYS and TRI. Thunder cannot be ruled out
but probability looks too low to warrant inclusion for tonight 
into the morning hours. By afternoon, the chances for thunder will
increase enough to include prob30 thunder groups at CHA and TYS, 
with thunder chances a bit lower at TRI. Shower and thunderstorm 
probabilities should be decreasing late in the period. 

&&

.PRELIMINARY POINT TEMPS/POPS...
Chattanooga Airport, TN             83  70  84  70 /  70  50  60  20 
Knoxville McGhee Tyson Airport, TN  83  68  86  69 /  80  20  50   0 
Oak Ridge, TN                       84  68  86  68 /  90  20  40   0 
Tri Cities Airport, TN              81  64  86  62 /  50  10   0   0 

&&

.MRX WATCHES/WARNINGS/ADVISORIES...
NC...Flood Watch through this evening for Cherokee-Clay.

TN...Flood Watch through this evening for Anderson-Bledsoe-Blount 
     Smoky Mountains-Bradley-Campbell-Claiborne-Cocke Smoky 
     Mountains-East Polk-Grainger-Hamblen-Hamilton-Hancock-
     Hawkins-Jefferson-Johnson-Knox-Loudon-Marion-McMinn-Meigs-
     Morgan-North Sevier-Northwest Blount-Northwest Carter-
     Northwest Cocke-Northwest Greene-Northwest Monroe-Rhea-
     Roane-Scott TN-Sequatchie-Sevier Smoky Mountains-Southeast 
     Carter-Southeast Greene-Southeast Monroe-Sullivan-Unicoi-
     Union-Washington TN-West Polk.

VA...Flood Watch through this evening for Lee-Russell-Scott VA-
     Washington VA-Wise.

&&

$$

DISCUSSION...Wellington
AVIATION...99


--- MBSE BBS v1.1.7.2 (Linux-x86_64)
 * Origin: Outpost BBS * Johnson City, TN (618:618/1)