textproduct: Jackson

KEY MESSAGES

- Frost/freeze conditions are anticipated again from tonight into Monday morning, especially in the valleys of eastern and southeastern Kentucky.

- Frost is possible again on Monday and Tuesday nights, primarily in the valley locations.

- Expect near-normal temperatures throughout the upcoming work week, with mostly clear skies and overnight ridge-valley temperature splits likely to continue for the foreseeable future.

UPDATE

Issued at 755 PM EDT SUN OCT 18 2026

A surface ridge of high pressure is in place this evening from the Northeast into the Appalachians and OH Valley to sections of the MS Valley. Meanwhile, the axis of upper level ridging extends from the Southern Appalachians into eastern KY and into sections of the Lower to Middle OH Valley. With the ridging remaining in place, clear skies are expected to continue, while winds will slacken overnight. This will set the stage for lows approaching the freezing mark and likely falling below the freezing mark in the typical sheltered valleys and hollows away from larger creeks, rivers, and lakes. Recent dewpoints in the 40s for valleys nearer larger bodies of water in the southeast pointed toward the likelihood for greater areal extent of fog in the more upstream locations within those basins. With that in mind, added greater coverage of patchy fog for these areas. Otherwise, grids were freshened up based on recent observations.

LONG TERM

(Tuesday through Sunday) Issued at 329 PM EDT SUN OCT 18 2026

The 18/12Z model suite analysis beginning Tuesday morning shows good agreement through the upcoming work week. Broad upper-level ridging will be situated over the heart of the CONUS with its axis initially roughly aligned with the Mississippi River. This upper level feature will continue to support robust surface high pressure sprawling across much of eastern North America, centered around an ~1035 mb high south of James Bay. North to northeasterly low-level flow will continue to filter down the Appalachians along the eastern side of the high through the new work week, keeping a dry, cool air mass in place over eastern Kentucky. Uncertainty increases next weekend regarding the persistence of the ridge as an upper-level trough may eject eastward from the Pacific and lead to its break down. Even so, a slim majority of the 00Z LREF members still favor the ridge holding firm into the last week of October.

In sensible terms, the persistent surface ridging and northerly to easterly flow will keep fair and seasonably cool weather across all of eastern Kentucky with only a slow moderating trend. Highs on Tuesday are forecast to range from the mid 60s to lower 70s, moderating into the upper 60s to mid 70s by next Sunday. Meanwhile, nighttime lows start off in the mid 30s to lower 40s on Tuesday night and only moderate slightly to the upper 30s to mid 40s by the weekend. Lingering patchy frost is probable Tuesday night into early Wednesday for the sheltered valleys, and additional isolated patchy frost cannot be entirely ruled out later in the week in the coldest sheltered hollows. Otherwise, at least patchy fog is likely along the mainstem rivers and larger tributaries on most nights.

AVIATION

(For the 00Z TAFS through 00Z Monday evening) ISSUED AT 814 PM EDT SUN OCT 18 2026

Surface and upper level riding will remain in place across the region through the period. This will lead to light winds and very few if any clouds. River valley fog, dense in some areas, is likely to develop by roughly 04Z and linger through as late as 13Z to 14Z. At this time, this is not expected to affect the TAF sites with any visibility reductions.

JKL WATCHES/WARNINGS/ADVISORIES

Frost Advisory from 1 AM to 9 AM EDT Monday for KYZ044-050-051- 058-059-068-079-083-084.

Freeze Warning from 1 AM to 9 AM EDT Monday for KYZ052-060-069- 080-085>088-104-106>120.