textproduct: Morristown

KEY MESSAGES

Updated at 117 AM EDT Tue Aug 11 2026

- Showers and thunderstorms will be possible each day through the end of the work week, with the best chance of rain during each afternoon.

- There will be potential for a few storms to become strong to severe each afternoon with damaging winds and localized flooding the main threats.

- Temperatures will be generally not be far either side of normal for this time of year.

DISCUSSION

Issued at 117 AM EDT Tue Aug 11 2026

A cluster of thunderstorms can be noted across portions of Ohio as latest satellite imagery paints mostly clear skies across the southern Appalachians this evening. Mostly clear skies will likely result in some patchy fog across CWA, though, latest HREF probabilities of visibility less than 4 miles is not nearly as widespread as what was observed this past morning. This is likely due to the lack of precip observed across the area today. While mostly dry, the NAM3km has been initializing the activity to our north fairly well this evening and suggest a few morning shower/storms cannot be ruled out in SW VA/NE TN, with the very low chance of some strong wind gusts.

On the synoptic scale, we are generally expected to remain in a northwest flow pattern through Thursday as we sit beneath that transition zone between a strong ridge axis to our west and a trough axis to our north and east. Unfortunately, this pattern promotes lower confidence levels when really trying to hone in on exact hazards and timing of expected rounds of showers and thunderstorms, as each round(or lack thereof) can impact the next.

Latest Hi-res guidance suggest the potential for convective initiation in the early to mid-afternoon. If these storms are able to develop, ample instability will promote potential for damaging wind gusts, isolated flooding, and perhaps small hail as the primary hazards. While I suppose the threat of a brief spin-up is not zero with the afternoon activity, shear is more borderline at that timeframe. A more pronounced vort max is expected to swing into the Ohio Valley this evening/tonight, with the potential for an MCS to bring increased coverage of showers and storms. Though timing is fairly broad with the latest HREF suite depicting really anytime between about 00-12Z, or some models not even initializing this second round. Damaging wind and flooding will remain the primary hazard, but with enhanced shear due to an increase in the low-level jet, a spin-up or two would be possible conditional on the activity not moving through too late into the overnight so that a surface inversion begins to develop. Additional rounds of showers and storms are possible Wednesday and Thursday, as more bouts of energy translate through mean flow, but timing is highly uncertain. With a warm and moist airmass, cannot rule out localized flooding and strong to damaging winds with any activity.

The upper level ridge will shift eastward Friday into the weekend, and while some precipitation chances continue, the chance for any organized MCSs trends downward while temperatures trend slightly warmer.

AVIATION

(06Z TAFS) Issued at 117 AM EDT Tue Aug 11 2026

Clear skies across the region is allowing some fog to form across SW VA and far NE TN. Incoming mid/high clouds from convection over the Ohio valley may prohibit the fog from becoming too dense, so have only taken KTRI down to 4SM VSBY with some LIFR bases, but I wouldn't be surprised to see that dip further. Otherwise, have included some TSRA in a PROB30 group at KTRI this afternoon and evening. There's enough uncertainty with timing and areal coverage of convection today so I decided to leave it out of the other terminals.

PRELIMINARY POINT TEMPS/POPS

Chattanooga Airport, TN 93 74 94 75 / 40 20 30 20 Knoxville McGhee Tyson Airport, TN 91 73 92 74 / 20 40 40 40 Oak Ridge, TN 91 72 92 73 / 20 30 40 30 Tri Cities Airport, TN 88 69 88 70 / 40 60 60 50

MRX WATCHES/WARNINGS/ADVISORIES

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