textproduct: Jackson

KEY MESSAGES

- Hot and humid weather persists at quite oppressive levels through the rest of the week, likely peaking on Thursday.

- Mostly dry weather is anticipated through Thursday, before chances for showers and storms return to end the week.

LONG TERM

(Thursday through Tuesday) Issued at 354 PM EDT TUE JUN 30 2026

Unfortunately, little relief from the heat is expected at the opening of the long term period. An upper level ridge will continue to be centered over the Central Appalachians, keeping weather hot and muggy across eastern Kentucky. Of note, Thursdays record high in Jackson (a measly 93 degrees) could be in jeopardy. NBM output suggests highs could generally range from the upper 90s to the low 100s across the forecast area; however, temperatures this high are not currently supported by 850mb temperatures in any model guidance. Given this trend, it is more likely that high temperatures should generally range from the mid to upper 90s across the forecast area, so MaxTs were nudged down slightly to account for this. Additionally, with such a hot and humid air mass in place, diurnally driven isolated convection cannot be ruled out, particularly in the southern portion of the forecast area. Associated cloud cover and precipitation could keep temperatures cooler than forecast in affected areas, but the majority of the forecast area should remain hot with limited overnight relief as dewpoints remain in the 70s.

Friday will bring the first indications of a pattern change as troughing generally becomes less amplified in the western CONUS and embedded impulses are able to finally push the upper level ridge axis to our east. With high pressure no longer directly overhead, temperatures will be marginally cooler than Thursday (largely in the mid 90s), although dewpoints will remain high. This will allow for a slight increase in diurnal convective coverage, with scattered storms possible on Friday afternoon and evening. Given a moist environment (with LREF mean PW values generally in the range of 1.6-1.7), any storm that develops could be capable of producing brief torrential downpours. However, given weak mid and upper level winds, shear will be so minimal that truly organized convection is not expected.

Looking into the weekend and early next week, a transition to a more active pattern and a gradual cooling trend is expected. Hot and humid conditions will generally continue through this weekend, with scattered storms possible each afternoon. On the Fourth of July specifically, highs are currently forecast to remain in the low 90s for much of the forecast area; however, with dewpoints remaining in the 70s, it will still be noticeably muggy for any outdoor activities, and scattered evening storms could become a problem for Independence Day. With ample atmospheric moisture (LREF mean PW values in the 1.6-1.8 range), torrential downpours will again be possible with any convective activity. To account for potentially high rain rates, the Weather Prediction Center has introduced a Day 5 Marginal Risk (Level 1/4) for Excessive Rainfall across eastern Kentucky, indicating the potential for isolated flash flooding. Additional rounds of rain will be possible through the end of the period as a frontal boundary approaches at the surface and the upper level pattern evolves towards increasing troughing and shortwave activity.

AVIATION

(For the 00Z TAFS through 00Z Wednesday evening) ISSUED AT 738 PM EDT TUE JUN 30 2026

With high pressure remaining across the region, diurnally-driven cumulus have largely dissipated but should return around 15Z. Valley fog is expected to develop again tonight and affect the typically favored valley locations between about 04Z and 13Z. At this point, TAF sites are not expected to be affected. Winds will remain light and variable through the period.

JKL WATCHES/WARNINGS/ADVISORIES

Extreme Heat Warning until 8 PM EDT Friday for KYZ044-050>052- 058>060-068-069-079-080-083>088-104-106>120.