950 
FXUS64 KMRX 061810
AFDMRX

Area Forecast Discussion
National Weather Service Morristown TN
210 PM EDT Wed May 6 2026

...New DISCUSSION, AVIATION...

.KEY MESSAGES...
Updated at 140 PM EDT Wed May 6 2026

- Widespread showers and storms through tonight.

- A conditional severe weather threat exists this afternoon and
  evening near the TN/GA border. Overall the odds are low, but the
  risk of damaging winds or even a tornado aren't zero.

- Heavy rains and an isolated risk of flooding could occur in the
  far south this afternoon and evening as well. But again, like
  the severe risk, the overall odds are low.

&&

.DISCUSSION...
Issued at 140 PM EDT Wed May 6 2026

An upper jet will strengthen over the Ozarks and Ohio valley this 
afternoon and evening, with shortwave energy moving ENE overtop a 
cold front situated from Kentucky, southwest over Middle Tennessee 
and northern Mississippi. Regional radar imagery show the CWA in a 
lull between morning convection and additional storms to our west, 
with visible satellite imagery showing some sun breaks and thinning 
of cloud cover across East Tennessee as well. And temperatures are 
responding in kind, with a nearly 10 degree increase in surface 
temps at Chattanooga the last couple of hours. All of this to say 
that model forecasts showing surface based CAPE values climbing into 
the 500-1,000 J/kg range later this afternoon in the south seem 
very reasonable, and with the shear (upwards of 50kt effective 
bulk shear), the conditional threat of severe storms remains in 
place there. Further north I think the odds are quite low.

The southern severe threat is not without uncertainty though. 
Current regional radar imagery matches the 12z NAM Nest fairly 
well for this hour. This model shows this cluster of storms over 
the WFO Huntsville forecast area moving east along the TN/GA 
border over the coming few hours, followed by additional 
development later this afternoon and evening in those same general
areas. The questions I have are, does this activity become severe
as it moves through our far southern areas here shortly...does 
this activity clear to the east quick enough that we can regain 
some surface instability later on...or finally, does it 
effectively stabilize the far southern areas heading into the late
afternoon and evening. If the latter, then our severe threat is 
quite low, if it exists at all. The other two scenarios are less 
clear. It would seem reasonable to assume that the thermal 
profiles along the TN/GA border show greater instability and an 
environment that would support stronger wind gusts making it to 
the surface. As for the tornado threat right now, it seems low as 
the VAD wind profile off HUN's radar doesn't show favorable 
conditions. That likely doesn't change in the near term in the 
southern TN valley either. Later this afternoon, forecast 
soundings show slightly better conditions but there's still
uncertainty. The threat seems to be confined along or just south 
of the TN/GA border. Further north perhaps some damaging winds 
could occur but CAM guidance doesn't show much in the way of 
stronger activity so the thought is that severe chances are 
limited to the south.

As far as chances for flooding problems, most guidance has shifted 
the heaviest rain south of our area. It's not out of the question we 
could see some isolated flooding issues due to training storms, 
especially from the far southern TN valley eastward into our NC 
counties where QPF is forecast to be highest. But overall it seems 
the threat is less than the last few days. 

The cold front behind all of this will push through the area late 
tonight. Rainfall should largely be wrapping up between 06z and 12z, 
but the upper jet doesn't pull off to the east until Thu afternoon 
so I wouldn't be surprised to see some showers lingering in mainly 
the mountains through midday or early afternoon as we transition to 
a NW flow region just off the surface. 

Dry conditions are expected late Thursday through Friday. Zonal flow 
aloft then brings another disturbance through the area Friday night 
into Saturday, but rain chances are questionable with that period as 
we're beneath confluent upper jet energy. Current NBM guidance 
doesn't have much in the way of rain chances and I'm inclined to 
think that's reasonable for now. But some guidance does bring some 
quick hitting rain to the area early Sat morning. Better rain 
chances exist later in the weekend as a synoptic scale trough works 
through the eastern CONUS. 

&&

.AVIATION...
(18Z TAFS)
Issued at 140 PM EDT Wed May 6 2026

Widespread SHRA and embedded TSRA (most likely at KCHA) will
spread across East Tennessee this afternoon and evening. Expect
most activity will wrap up around or shortly after 06z tonight,
but some showers may linger into the morning hours. As for flight
categories, expect a mix of MVFR and IFR conditions overnight as
the front moves in from the west. A return to VFR categories
doesn't seem likely until after 18z tomorrow.

&&

.PRELIMINARY POINT TEMPS/POPS...
Chattanooga Airport, TN             57  72  47  74 / 100  10   0   0 
Knoxville McGhee Tyson Airport, TN  54  69  44  72 /  90  20   0   0 
Oak Ridge, TN                       53  70  43  72 /  90  10   0   0 
Tri Cities Airport, TN              52  65  40  69 /  90  40   0   0 

&&

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

$$

DISCUSSION...CD
AVIATION...CD


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