textproduct: Louisville

KEY MESSAGES

* Cool and dry weather tonight with isolated frost in our northeastern-most river valleys possible (<20%).

* Warming trend will begin on Tuesday with highs in the mid 70s to near 80 degrees and above normal temperatures through at least the weekend.

* A chance of showers is possible across the northern Bluegrass on Wednesday. The next weather system that will bring significant precipitation to the region will arrive late Friday and into Saturday.

SHORT TERM /THROUGH TUESDAY/

Issued at 306 PM EDT Mon Apr 20 2026

===== Tonight - Tuesday Evening =====

Currently, skies are clear except for some lingering broken sky cover near Casey County, with light winds generally out of the north to northeast. Low to mid level high pressure is parked overhead central KY and will keep us dry this evening and through the overnight hours. Winds will be very light this evening as a result with clear skies overhead. Because of these calm conditions, temperatures will cool quickly overnight in the mid 40s to mid to upper 30s in the northeast.

A decent temperature gradient will occur SW to NE due to the return SW flow coming in from the high pressure sagging to our south. May need to issue an SPS for our far northeastern counties on account of patchy frost possible in isolated river/creek valleys (<20%), but this threat is low. Otherwise, everyone remains frost free with temperatures quickly warming into the mid 70s to isolated low 80s in the southwest. Clouds begin streaming in from the northwest during the early afternoon, though they'll be more of something to see with little impacts to conditions at the surface. SW wind gusts pick up throughout the day near 20-25 MPH as a low level jet moves in from the north but otherwise, tomorrow is a pleasant mostly sunny day.

LONG TERM /TUESDAY NIGHT THROUGH MONDAY/

Issued at 306 PM EDT Mon Apr 20 2026

Tuesday Night - Thursday Night...

Upper ridging will be in control of the central CONUS through mid week, with the axis gradually shifting eastward over our area through late week. Overall, this will be an increasingly warm and dry pattern, however a couple of things worth pointing out.

On Tuesday night into Wednesday, NW flow aloft will be present across our area, downstream of the upper ridge axis. A shortwave embedded in the NW flow aloft, and its associated surface low will pass through the Great Lakes dragging a cold front toward our NE CWA. Here, the feature is expected to stall out as it becomes more parallel to the upper flow. Most of the activity looks to stay just NE of our CWA boundaries, however will have to continue carrying some small chances along and north of a line from Salem, IN to Frankfort, KY to Lexington, KY line. Everyone else should stay dry and mild under better influence from the upper ridge axis starting to build in.

Temperatures will be above normal in the upper 70s and low 80s with lows in the 50s. By Thursday night, milder lows in the upper 50s and low 60s are expected.

Friday - Saturday Night...

Friday looks to start out dry with the upper ridge axis still overhead, however this feature will be sliding east as a line of showers and storms looks to approach ahead of a cold front later Friday into Friday night. Forecast soundings do show at least some modest instability and deep layer shear profiles, so do expect there could be a thunderstorm threat with this as well. Our antecedent dry airmass, retreating subsidence from the upper ridge, and time of day all may contribute to a weakening of upstream showers and storms as it approaches, although can't rule out this could have some gusty winds with either a cold pool push and/or just enough shear for some organization.

Depending on exact timing, showers and/or a few storms will likely linger into the first part of Saturday as the cold front stalls and washes out over or near the area. There is also a trailing shortwave ejecting out of the central Plains across the zonal flow over the southern two-thirds of the US for Saturday. This feature could also add to lingering shower and storm chances for Saturday/Saturday night with some possible triggering along the old convectively reinforced cold front/outflow from the night before. Temps in the upper 70s and low 80s still expected here, but much will depend on the shower and storm activity for this time.

Sunday - Monday...

Not all that high of confidence for the late weekend to early week time frame, however there is some signaling for a strong shortwave ejecting out of the central CONUS into the upper Midwest, along with its associated surface low by Monday. Showers and storms would develop ahead of the shortwave trough axis and trailing cold front, with some instability to work with as well. Shear profiles have a good chance of being favorable for organized updrafts, so can't rule out that this system could come with a strong storm threat. Something to watch as we enter early next week.

AVIATION /18Z TAFS THROUGH 00Z WEDNESDAY/

Issued at 129 PM EDT Mon Apr 20 2026

VFR conditions will persist through the whole TAF period. Light N-NE winds will continue becoming light and variable after sunset. Overnight, high pressure builds in keeping everyone clear and dry with calm to near calm winds. After sunrise, high pressure moves southeast shifting winds from the SW gusting 20-25kts towards the end of the TAF period (after 16Z). High level FEW-SCT clouds will move in by Tuesday afternoon as well with VFR conditions expected still.

LMK WATCHES/WARNINGS/ADVISORIES

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