textproduct: Louisville

KEY MESSAGES

* Frost Advisory and Freeze Warnings remain overnight into tomorrow (Sunday) morning for overnight lows in the mid to low 30s.

* Dry weather expected all of next week, with temperatures gradually climbing back into the 70s.

UPDATE

Issued at 925 PM EDT Sat Oct 17 2026

Early evening satellite imagery shows skies have cleared across the region. Looking at temps via personal weather stations, ASOS, and the KY Mesonet, temperatures ranged from the upper 30s and lower 40s in the more protected valley locations to the mid-upper 40s on the ridges. Surface winds have been a little slower to come down and that is likely delaying radiational cooling to an extent.

For the overnight period, clear skies are expected. Winds should come down overnight, but some of the latest data suggests that a light breeze may continue well into the night which could hamper idealized radiational cooling, especially in more exposed areas. As for min temperatures overnight, lows will solidly be in the 34-38 degree range. The highest risk of at least several hours of 32 or below will be across the northern/northeastern Bluegrass within the freeze warning area. Another potential area of 32 or below will be across portions of south-central IN and perhaps into portions of northwestern KY.

The current headlines continue to look good with a widespread frost expected and a freeze in the northeastern Bluegrass region. Some of our more protected spots in the frost advisory area could hit the freezing mark for several hours. We still believe that frost will be the primary impact here, so no headline changes are planned at this time.

DISCUSSION

Issued at 306 PM EDT Sat Oct 17 2026

===== Frost and Freeze Headlines Overnight into Tomorrow AM =====

Cold air advection in place today over the Ohio Valley has kept temperatures mainly in the mid 50s with upper 50s to near 60 across the south and low 50s in the Bluegrass due to stubborn lingering cloud cover. Sfc high pressure over the central US will continue to build over the Ohio Valley tonight into tomorrow. This will help to clear out any lingering cloud cover and result in light winds overnight. Strong radiational cooling is still expected once skies clear and winds become light. We will update both the Frost Advisory and Freeze Warning with no changes at this time with the caveat that a few counties along the current Freeze Warning may need to be added. Some of the current hesitation was due to probabilities for lows at or below freezing tomorrow morning in the HREF and NBM had decreased with model guidance suggesting some light winds may linger overnight. Widespread morning lows in the mid to low 30s is still anticipated across central KY and southern IN.

===== Dry & Seasonal Weather All of Next Week =====

A fairly stagnant weather pattern will be in place through most of the week before we see some changes by the end of the week and into next week. Main flow of the jet stream will be fairly zonal along and just north of the US/Canada border. Two cut-off lows, one over the Atlantic off the Mid-Atlantic coast and one in the Pacific off the California coast will lock upper ridging over the central US. This will allow for sfc high pressure to keep weather mainly dry along with temperatures returning to near to slightly above mid to late October normals with highs in the low/mid 70s.

AVIATION /00Z TAFS THROUGH 06Z MONDAY/

Issued at 706 PM EDT Sat Oct 17 2026

Earlier afternoon Cu field has diminished and clear skies are expected for this evening and into the overnight period. Winds will remain out of the northeast at 2-4kts but will gradually shift to the east toward dawn Sunday. VFR conditions are expected on Sunday with winds veering to the southeast during the day.

LMK WATCHES/WARNINGS/ADVISORIES

KY...Frost Advisory from 1 AM EDT /midnight CDT/ to 9 AM EDT /8 AM CDT/ Sunday for KYZ023>035-038>040-045>048-053>057- 061>067-070>078-081-082. Freeze Warning from 1 AM to 9 AM EDT Sunday for KYZ036-037- 041>043-049. IN...Frost Advisory from 1 AM EDT /midnight CDT/ to 9 AM EDT /8 AM CDT/ Sunday for INZ076>079-083-084-089>092.