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KEY MESSAGES

* Mostly cloudy skies are expected today with some morning showers. Abundant cloud cover will likely limit instability and result in less shower and thunderstorm chances.

* A period of warm, dry, and breezy conditions are expected for Friday.

* Strong cold front will bring widespread showers and thunderstorms to the region for Saturday. There remains a low-end risk of strong storms with this system. Much cooler air will arrive late Saturday and Sunday with a patchy frost likely Monday morning.

SHORT TERM /THROUGH FRIDAY NIGHT/

Issued at 339 AM EDT Thu Apr 16 2026

Early morning observations reveal partly to mostly cloudy skies across the region with temperatures in the mid-upper 60s on the ridges and lower-mid 50s in the more protected valleys. Area radars continued to show dry conditions across the region for the time being. For the remainder of overnight period, generally quiet weather is expected for the next few hours. Ongoing line of convection out near St. Louis will continue to move slowly eastward across southern IL this morning. This activity may make it into our far northwest counties by sunrise. Expect overnight temperatures to remain in the mid-upper 60s in most areas, with the more protected valleys remaining in the mid 50s.

For today, quite a bit of mid-high level cloud cover will move across the region during the morning hours. Decaying line of showers will attempt to push through the region. However, latest round of convective allowing guidance continues to trend drier in recent runs. Overall, it appears that some scattered rain showers will be possible in the I-65 corridor and point west this morning. Some thinning of the cloud cover may occur by mid-late afternoon and that could result in some convective redevelopment across the eastern sections of the forecast area (mainly east of the US 27/127 corridor). A look at proximity model soundings show steep low-level lapse rates across the region with about 25-30kts of bulk shear. Soundings continue to show a bit of a warm nose above 700mb which may keep convection from getting sufficiently deep. Should deep convection develop, brief heavy rainfall, lightning, and gusty winds would be the main threats. The expected cloud cover will likely keep temperatures a bit cooler today with highs of 75-80 expected across the region.

For this evening and overnight, will have to watch areas to our southwest where some of the data suggests that a trailing convective outflow boundary combined with differential heating may lead to another batch of strong/severe convection firing across southern MO and into northern AR. This activity may scrape across southwest KY and could impact our southern zones (prob around 30%). Otherwise, some partial clearing is expected with lows falling back into the upper 50s to around 60.

For Friday and Friday night, shortwave trough axis looks to move across the Mid-Atlantic while upper ridging rebuilds across the deep south into the Ohio Valleys. A broad southwest flow is expected across the region with mostly sunny skies. This pattern should allow temperatures to top out in the 83-88 degree range with breezy winds out of the southwest. A rather extensive area of strong/severe convection is expected from the southern Plains northeast through the upper Midwest and western Great Lakes Friday afternoon/evening. This activity will likely continue into the overnight hours with clouds increasing across our region and a chance of showers in areas west of I-65 prior to dawn Saturday. Overnight lows Friday night will be in the mid-upper 60s.

LONG TERM /SATURDAY THROUGH WEDNESDAY/

Issued at 339 AM EDT Thu Apr 16 2026

Saturday and Saturday Night...

For Saturday, a large scale upper trough axis over the upper Midwest will shift through the Midwest, Great Lakes, and the OH/TV Valleys during the day on Saturday. A large cold front will accompany this trough axis and this feature will be the focus of shower and thunderstorm activity. Ahead of the front, the pressure gradient will increase and that will lead to gusty southwest winds of 25-30 mph during the morning and into the afternoon hours. An extensive area of cloud cover will spread across the Ohio Valley during the day, mainly impacting areas west of the I-65 corridor. Highs along and west of the I-65 corridor look to warm into the low-mid 70s, with upper 70s to near 80 in areas east of I-65.

The latest guidance continues to push the front in a little faster than in previous forecast. As of this writing, the surface cold front should be pushing across the IN/IL border by Saturday morning and then crossing the Ohio River sometime between 18-21Z and then slowly pushing into the Bluegrass region during the late evening hours. Ahead of the front, a band of widespread showers and thunderstorms is expected. Instability may be quite limited in areas west of I-65 due to extensive cloud cover. However, in areas east of I-65, a pool of low level moisture will be available and some diurnal heating may allow MLCAPE values to reach 800-1000 J/kg. While the instability may be modest, model proximity soundings continue to show rather strong low-mid level flow across the region which would support organized convection. Overall flow is unidirectional so convection would tend to be more linear in nature with damaging winds being the main concern. Best combination of shear/instability looks to be just northeast of the CWA from across mainly southern Ohio into portions of West Virgina where the new SPC day 3 slight risk is located.

The highest chances of showers and storms on Saturday continues to be from the mid-morning through the late afternoon as the frontal boundary pushes through the region. Overall confidence in the frontal boundary timing has increased a bit with this forecast as most model guidance has the frontal boundary east of the I-65 corridor by the evening hours. While the front may be pushing through the Bluegrass region at that time, extensive cloud cloud cover and light rain showers may persist until mid-evenig or so. Behind the front, the winds will shift to the northwest and will remain gusty through the evening. Temperatures are expected fall sharply behind the front, with afternoon readings falling from the 70/80s to the low-mid 50s by mid-evening. Convection looks to move out of the forecast area by midnight or so with temperatures falling into the lower 40s by sunrise Sunday.

Sunday through Wednesday...

Upper trough axis will pivot through the region on Sunday with a much cooler/drier airmass filtering into the region through the day. Highs on Sunday will likely remain in the upper 50s in the Bluegrass region with lower 60s elsewhere. High pressure will pass over the region Sunday night and there is an increasing risk of frost across the area, especially in the Bluegrass region where temperatures may dip into the middle 30s. Highs will begin to moderate on Monday with readings in the lower 60s in the Bluegrass with mid-upper 60s in the I-65 corridor and points west. Highs will warm into the 70s for Tuesday and Wednesday with a slight chance of showers/storms on Wednesday.

AVIATION /18Z TAFS THROUGH 00Z SATURDAY/

Issued at 151 PM EDT Thu Apr 16 2026

Mainly VFR weather continues through this forecast period. A band of BKN clouds near 5 kft will push east across the eastern half of KY this afternoon and evening. Scattered showers and perhaps a few thunderstorms will be possible near LEX and RGA through mid- afternoon before this activity pushes east of the area.

Gusty winds from the southwest continue through 23Z before diminishing. An upstream cluster of convection developing over southern MO is expected to move through western KY/TN later this evening. BWG could see a thunderstorm around 01-02Z (30-40% chance). SHRA/TSRA chances in south-central KY diminish fairly quickly after 03Z, with skies clearing after that. Look for additional SCT cirrus heading into Friday morning, with SCT-BKN cumulus developing Friday afternoon.

LMK WATCHES/WARNINGS/ADVISORIES

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