textproduct: Louisville

KEY MESSAGES

* Unseasonably warm temperatures this weekend, with highs in the 70s and 80s expected.

* Increasing threat of strong to potentially severe storms ahead of a cold front Sunday evening and overnight. A Slight Risk (Level 2/5) has been issued for northern portions of the CWA. Large hail and damaging winds are the main severe hazards.

* Cooler and mainly dry conditions are expected early next week.

UPDATE

Issued at 1100 AM EDT Sat Mar 21 2026

The remnants of a cold front have settled across central KY this morning, with a notable north-south gradient in temperatures and dewpoints seen in latest KY mesonet obs. Across south central KY, dewpoints remain in the mid-to-upper 50s as drier air was not able to push into these areas with the front. While scattered mid- and high-level clouds are resulting in filtered sunshine across most of the region, this has not stopped temperatures from warming quickly across the region so far this morning.

The main thing we're watching over the next 6-12 hours will be if any showers and storms can develop across south central KY this afternoon within the more moist/unstable environment. Soundings do show 500-1000 J/kg of MLCAPE, though a capping inversion around 5k ft will hinder convective initiation in most locations. There is a weak mid-level vort lobe which will cross the region this afternoon and evening that could provide modest forcing for ascent in addition to weak convergence near the remnant front. If any storms are able to develop, wind shear is not overly impressive, but you could see some gusty winds and small hail in addition to heavy rain lightning. The main time for any shower/storm generation should be after 2 PM CDT, with any cells that do develop pushing into TN later this evening.

The forecast is generally on track at this time. Freshened the near- term grids with the latest NBM PoPs, which did increase slightly across southern KY this afternoon. Temperature progs are on track for highs in the upper 70s and low 80s this afternoon.

SHORT TERM /THROUGH TONIGHT/

Issued at 512 AM EDT Sat Mar 21 2026

Sfc boundary is currently positioned across the state of KY this morning. You can see this per the KY Mesonet with the subtle wind changes. A few high clouds continue to stream over the area within the northwest flow aloft. While this boundary will meander over the area today and tonight, the majority of the forecast this weekend will be dry and unseasonably warm. Sfc boundary will continue top push south and stall for a brief period this morning along the KY/TN border. It will then lift back north as a weak warm front later on this afternoon and evening. It will be another nice yet unseasonably warm day as highs will be in the upper 70s to low 80s this afternoon. There is just a very low end PoP chance along the KY/TN border thanks to the lingering sfc boundary but most should remain dry.

Quiet and mild weather will continue overnight with clear skies and lows near 60 degrees.

LONG TERM /SUNDAY THROUGH FRIDAY/

Issued at 512 AM EDT Sat Mar 21 2026

Sunday and Sunday Night...

We continue to look very warm, with a few locations like LEX and FFT challenging record highs as high will reach the low/mid 80s during the afternoon. Highs will be running 25+ degrees above seasonal normals for this time of year. We are also still under a Slight Risk or 2 out of 5 for the potential of severe weather Sunday evening.

A sfc cold front will stretch from Kansas to Lake Erie Sunday morning as a sfc low over will be exiting the Great Lakes. Winds will increase ahead of this system helping to increase moisture as well as boost temperatures over the Ohio Valley during the day.

Sfc cold front will approach and be near the Ohio River by Sunday evening. The upper level trough axis and associated upper-level jet will be working through the Great Lakes by the same time. As was mentioned in the AFD yesterday and noticed previously, model soundings continue to show a warm stable layer between 850-700 mb. As was stated in the previous discussion, this should help to cap convection development during the afternoon hour of Sunday, but as the front approaches from the north, the warm layer should erode some allowing for cells and convection to develop. Overall thinking remains relatively the same. Initially, discrete supercell develop is likely early in the event and continue to be more to our north- northeast Sunday afternoon thanks to the ongoing capping. By evening, as the capping erodes, we will still have fair amount of ML CAPE around 1000 J/kg, with the 0-6km shear to be around 45-50kt, and steep mid-level lapse rates of around 7.5 deg C/km. This set up looks to be more of a hail threat and gusty winds than tornadoes.

The Slight risk continues to highlight the highest threat across southern IN and along the Ohio River and the I-64 corridor. The severe threat across our area will come down to placement of the front Sunday afternoon/early evening when we have the best daytime heating and how strong the stable layer will be over the area.

Monday - Thursday...

Behind the cold front, a couple days of dry and cooler weather are expected for Monday and Tuesday as temperatures fall back into the 50s and 60s. NW flow aloft will continue into the middle of next week, at which point weak perturbations within the upper wave pattern may be able to support light rain chances. As we get later into next week, ensembles tend to support a warm up for Thursday before another cold front passes through the region before next weekend. Timing and intensity of the late week system varies between models, so confidence in specifics is fairly low at this time.

AVIATION /12Z TAFS THROUGH 18Z SUNDAY/

Issued at 654 AM EDT Sat Mar 21 2026

Sfc boundary will meander across southern KY and norther TN this morning before slowly drifting back north. A few high clouds have been sliding over the area but it remains VFR. Winds will be lighter than the last few days and variable through the morning before becoming more southwest. VFR conditions remain through the forecast.

LMK WATCHES/WARNINGS/ADVISORIES

KY...None. IN...None.