textproduct: Morristown

KEY MESSAGES

Updated at 737 PM EDT Sat Jul 25 2026

- Scattered showers and storms are expected tonight. If multiple storms track over one location, isolated flooding will be possible.

- A warming trend begins tomorrow into the new work week. Monday and Tuesday will be the hottest days as heat indices in the mid 90s to low 100s become more commonplace, especially in the central and southern valley.

- Additional periods of isolated to scattered showers and storms are possible Monday and Tuesday. At this time, Tuesday afternoon and evening holds the greatest potential to have a few strong to severe storms with gusty winds the primary hazard.

- Mostly dry conditions with slight improvements to the heat and humidity are expected mid to late week.

DISCUSSION

Issued at 253 PM EDT Sat Jul 25 2026

A ridge axis remains centered well to our west while bouts of energy will rotate through mean flow aloft this afternoon and tonight. This will amplify troughing over the Mid-Atlantic into the southern Appalachians. H85 and higher altitude flow will see minor enhancements in response to the increasing vorticity advection tonight. Because of this, the HREF suite depicts developing scattered showers and storms across the region.

There will be a low risk of isolated flooding through the night. Aspects of the atmosphere in favor of isolated flooding will be high freezing-levels, anomalous PWATs, skinny CAPE profiles, and a few locations that remain with poor antecedent soil conditions. Working against the threat of isolated flooding is storm motion and lack of a surface boundary to train along. Additionally, latest RAP and NAMBufr soundings both depict a rather dry atmosphere at ~550mb and higher, suggesting limited depth of saturation.

Sunday afternoon looks to be mostly dry, though an isolated shower or storm cannot be totally ruled out. By Sunday night into early Monday morning CAMs are suggest a MCS progressing through northern KY and southward through portions of central and East Tennessee. This activity moves quite quick so flooding should not be of concern. The main focus will be keeping an eye on the potential for some strong to damaging wind gusts. NAM soundings depict a fairly stout low-level inversion so confidence is low that damaging gusts could make it to the surface. Will have to keep an eye on how the potential CAPE gradient plays out alongside timing trends.

A more potent shortwave is expected to promote development of an upper low over the eastern Great Lakes and Mid-Atlantic Tuesday into Wednesday. A surface low develops in response, and an associated cold front will bring increasing chances for showers and storms. NAMBufr soundings have quite an impressive thermodynamic profile at least for Tuesday afternoon, but timing of the storms may not necessarily work out to tap into peak heating and the latest hi- resolution guidance does not quite make it into those overnight hours. LREF joint probabilities of MUCAPE 1500+ J/kg and shear 30+kts are generally around 40 to 60% in our northeastern locations where a day 4 Slight risk is currently in place. Primary hazard would be damaging winds.

Regarding temperatures, Sunday through Tuesday will lean hot & humid. Heat indices will be greatest Monday and Tuesday, with near to low 100 degree values expected to creep into the central valley. Post FROPA, mostly dry and slightly cooler/less humid conditions are expected mid to late week.

AVIATION

(00Z TAFS) Issued at 737 PM EDT Sat Jul 25 2026

Radar is quiet currently but activity is expected to pick up in the overnight hours. Showers and possibly a few storms will be isolated to scattered mainly from midnight until daybreak. MVFR CIGs are likely at TRI and TYS late tonight through the morning hours. Some fog is possible but dense fog is unlikely. Shower activity is expected to be isolated tomorrow afternoon.

PRELIMINARY POINT TEMPS/POPS

Chattanooga Airport, TN 73 91 72 93 / 60 20 20 30 Knoxville McGhee Tyson Airport, TN 71 88 71 90 / 80 30 30 30 Oak Ridge, TN 70 88 70 90 / 80 20 20 30 Tri Cities Airport, TN 66 84 66 86 / 60 50 20 20

MRX WATCHES/WARNINGS/ADVISORIES

NC...NONE. TN...NONE. VA...NONE.