textproduct: Jackson

KEY MESSAGES

- Multiple rounds of showers and thunderstorms are possible through this evening. Damaging wind gusts could occur in the strongest storms.

- A Flood Watch is in effect through this evening east of I-75. Torrential downpours on saturated ground pose a risk for isolated to scattered flash flooding.

- Dry weather returns Tuesday before another cold front brings additional thunderstorm chances Wednesday evening through Thursday, followed by cooler temperatures late in the week.

LONG TERM

(Tuesday night through Sunday) Issued at 456 AM EDT MON AUG 17 2026

Dry weather will persist for most of Wednesday as surface high pressure translates through the Central Appalachians. In its wake, an upper level trough will be digging across the Great Lakes and supporting a cold front sagging across the Ohio Valley. By Wednesday evening, the front will approach eastern Kentucky and rain chances will return to the JKL CWA. Of note, some models depict an additional shortwave traversing the base of the trough (roughly centered over the Ohio Valley) around the time frontally forced convection approaches, or perhaps slightly before. This enhanced mid level flow may elevate shear somewhat, and depending on frontal timing, instability may also be adequate for stronger storms, although model spread remains quite high at this time. Any risk for severe weather (or lack thereof) remains dependent on how these ingredients line up, with overall risk looking quite low at this time. Meanwhile, a moist air mass will be in place ahead of the front, with LREF mean PW values generally in the range of 1.6-1.7 in (roughly 80th percentile or higher compared to climatology). This, in addition to potentially enhanced convective coverage if shortwave energy interacts with the front, could allow for at least isolated instances of flash flooding. Again, model variability remains very high at this stage, but WPC has already outlined northwestern portions of JKL area in a Day 3 Marginal (Level 1/4) Risk for Excessive Rainfall on Wednesday, and an additional Day 4 Marginal Risk on Thursday as the system sags south. Guidance does suggest the front will slow as it passes through the southern portion of our area and into Tennessee. Exactly how quickly this boundary progresses is still a source of uncertainty, but rain chances have been maintained through Thursday to account for this slowing motion. Any hydrological concerns will also be dependent on the speed of this frontal passage in addition to the extent of convective coverage.

Following the frontal passage, troughing will continue to amplify, eventually digging all the way into the Southeast as ridging retreats towards the Four Corners region. This will usher in cooler weather, with high temperatures as low as the upper 70s possible for some locations on Friday. Additional impulses will keep at least scattered showers and storms in the forecast each day, with rain chances generally peaking in the afternoon/evening.

AVIATION

(For the 06Z TAFS through 06Z Monday night) ISSUED AT 153 AM EDT MON AUG 17 2026

Aside from highly isolated weak convection, VFR conditions were noted over the terminals at the 06Z TAF issuance. Given recent rainfall, radiation fog formation is possible in the most sheltered valley locations early this morning, but modest low- level winds just off of the surface are likely to keep any more widespread fog formation in check. A cold front will approach the area during the daylight hours Monday with two or more rounds of convection possible. The first round of storms is over the Lower Ohio Valley and could reach more northern terminals by daybreak. Guidance continues to struggle with the evolution of this system, so forecast confidence in impacts at the terminals is somewhat low. Another round of convection is then expected during the afternoon and evening hours just ahead of/along the cold front. Winds will generally be light and variable early this morning, becoming southwest after daybreak before shifting northwest late in the day behind the cold front. Winds will generally remain around 10 kts or less, but could be locally strong and erratic near thunderstorms.

JKL WATCHES/WARNINGS/ADVISORIES

Flood Watch through this evening for KYZ044-050>052-058>060-068- 069-080-086>088-104-106>120.