textproduct: Louisville

KEY MESSAGES

* Strong cold front will push across the region today bringing widespread showers and a few thunderstorms to the region. There is a low risk of strong storms along and east of the I-75 corridor. Rain showers will continue into mid-evening.

* Much cooler and drier weather is for the last part of this weekend and into early next week. Frost is likely across southeast Indiana and into the Bluegrass region of central Kentucky Monday morning.

* A warming trend commence by mid-week with the next chance of precipitation toward the end of next week.

UPDATE

Issued at 1052 AM EDT Sat Apr 18 2026

Widespread light to moderate showers have developed east across the I-65 corridor this morning, with partly sunny skies noted east of I- 65 across the Bluegrass and Lake Cumberland regions. Temperatures have risen into the mid 70s ahead of the band of showers and thicker cloud cover.

The leading edge of the showers now pushing east of I-65 is roughly along a previous convective outflow boundary. This leading edge is showing signs of convective redevelopment on radar and satellite imagery. MLCAPE should soon increase into the 250-500 J/kg range along the I-75 corridor. This modest buoyancy could be enough to support a few strong to severe storms late morning into early afternoon in the Bluegrass Region. Strong deep-layer SW flow will support effective bulk shear of 50 kts across the eastern CWA into the afternoon hours. This is plenty for organized convection, so there remains a low-end risk (Marginal in the SPC Day 1 Outlook) for localized damaging wind gusts in the I-75 corridor/far eastern CWA. The severe risk is really limited by overall buoyancy and limited residence time of the favorable environment before rain showers and clouds overspread the eastern CWA, which will stabilize the low- level environment and eliminate the severe storm risk.

SHORT TERM /THROUGH SUNDAY NIGHT/

Issued at 311 AM EDT Sat Apr 18 2026

Early morning observations reveal partly to mostly cloudy skies across the region. Temperatures ranged from the low-mid 60s out in the I-75 corridor to the lower 70s along and west of I-65. Area radars remain generally echo free at the moment. Surface analysis shows a cold front from central IL extending southwest into southwestern MO and moving steadily east. A widespread band of showers and some thunderstorms was accompanying the front. For the remainder of the overnight hours, quiet weather is expected. A few showers will move into southwestern IN and our northwest CWA toward dawn.

For Today, upper level trough axis over the northern Plains will move through the Midwest and into the Great Lakes tonight. At the surface, aforementioned cold front extending from IL into southwest MO will continue to move eastward into IN/KY. Numerous rain showers with a few embedded thunderstorms will move into southern IN and western KY this morning and will gradually overspread the region by late morning and into the afternoon hours. Widespread cloud cover and anticipated precipitation will limit diurnal heating today. High temperatures will warm into the upper 60s/lower 70s along and west of the I-65 corridor. Highs in the low-mid 70s with a few upper 70s near the I-75 corridor are expected. Instability across the region will quite limited today due to the ongoing cloud cover, so strong storms are not expected this morning. Some restrengthening of storms could occur over our far eastern areas this afternoon where slightly better heating occurs. SPC has removed the marginal risk of severe from much of the region and only keeps our far eastern areas in a marginal risk this afternoon. Main threats with any storms this afternoon would be heavy rainfall, gusty winds, and lightning.

Surface cold front still looks to sweep across the I-65 corridor between 200-400 PM EDT. Ahead of the front, winds will be breezy from the southwest, but a quick shift of winds to the northwest is expected behind the front. Behind the front, widespread low clouds and showery precipitation is expected to continue through the afternoon and into the mid-evening hours before diminishing by midnight. Temperatures will cool off rapidly behind the front with temperatures falling into low-mid 50s by early evening. By mid- evening temps will fall into the upper 40s/lower 50s, with overnight lows eventually dropping into the upper 30s by Sunday morning.

Upper trough axis will rapidly advance eastward and pass through the region during the day on Sunday. An expansive area of high pressure will build into the region from the west. Partly sunny skies are expected for Sunday with highs warming into the upper 50s to around 60 in the Bluegrass with low-mid 60s in the I-65 corridor and points west. Clear skies and light winds are expected for Sunday night. This setup will likely bring areas of frost to southeastern Indiana and the Bluegrass region of central Kentucky late Sunday night and Monday morning. Sunday night lows will drip into the mid 30s in the Bluegrass with upper 30s to the lower 40s elsewhere.

LONG TERM /MONDAY THROUGH FRIDAY/

Issued at 311 AM EDT Sat Apr 18 2026

As we move into next week, the upper air pattern across the CONUS will start off with troughing in the east and troughing off the western US coast. In between, a mid-level ridge is expected to develop across the central Plains. This ridge axis will slowly advance eastward keeping the Ohio Valley in a northwest flow aloft for the first half of the week. By mid-late week, the west coast US trough is expected to move inland and into the Rockies before amplifying across the Plains. Another frontal boundary will push across the Plains resulting in an uptick of convection from the MO Valley northward into the Midwest by Friday and this activity will likely move into our region by late Friday and into Saturday.

Highs on Monday will remain in the upper 50s across the Bluegrass region with low-mid 60s in the I-65 corridor and point west. A broad southerly flow is expected to develop by Tuesday which will allow temps to warm back well into the 70s by Tuesday and into the upper 70s to near 80 by Wednesday. Highs in the upper 70s/lower 80s are expected for Thursday and Friday.

AVIATION /18Z TAFS THROUGH 00Z MONDAY/

Issued at 155 PM EDT Sat Apr 18 2026

Scattered light rain showers continue to stream northeast across the region. The sfc cold front is through HNB and is now draped NE to SW through southern IN and western KY. Cold front will sink southeast through the remaining TAF sites this afternoon. Precip coverage is diminishing this afternoon right along the cold front, so a lull in light rain is expected this afternoon before additional light, post- frontal showers develop this evening.

A narrow band of low clouds immediately behind the front will push southeast through the area this afternoon and early evening. High confidence in low-end MVFR ceilings (1500 ft), with low confidence in brief IFR (800 ft) ceilings. Other than HNB (which has already seen brief IFR), BWG appears to have the best chance at very brief IFR conditions. Light rain showers will persist through late this evening, with mainly dry conditions overnight. Clouds will clear from NW to SE early Sunday morning.

LMK WATCHES/WARNINGS/ADVISORIES

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