textproduct: Louisville

KEY MESSAGES

* Mostly cloudy skies are expected across the region today. Scattered rain showers are likely in areas along and east of I-75 this afternoon. Temperatures will top out in the upper 60s to around 70.

* Clouds will slowly mix out Thursday with highs warming back into the lower 70s.

* Crisp/cool mornings are expected for Friday/Saturday mornings where lows may bottom out in the lower-mid 40s across the Bluegrass region.

SHORT TERM /THROUGH THURSDAY NIGHT/

Issued at 314 AM EDT Wed Sep 23 2026

Satellite and observations reveal mostly cloudy skies across the region this morning with temperatures in the lower 60s. For the remainder of the overnight period, a mix of low clouds and some patchy fog and drizzle will continue across the region with temperatures remaining in the lower 60s through sunrise.

For today, low clouds are expected to remain entrenched over the region as an upper level trough axis moves through the region. At the surface, an inverted surface trough will be found from eastern TN and into eastern KY. These two features will lead to an extensive area of showers and a few thunderstorms, mainly over central and eastern Kentucky. Locally, the best chances of rain will be along/east of the US 27/127 corridor with the highest chances of rain being over in the I-75 corridor and points east.

NBM guidance hasn't handled this low cloud situation all that well with respect to temperatures. Therefore we have gone with the cooler guidance and very close to the 23/00Z HREF which will yield highs in the upper 60s to around 70 in most locations. Lows tonight will cool into the upper 50s to around 60 in most locations.

Moving into Thursday, upper trough axis is forecast to move off to the east with the trough axis closing off into an upper level low over the Mid-Atlantic region. The upper flow will be blocky over the eastern US with a northerly to northeasterly flow expected over the Ohio Valley. The main forecast challenge on Thursday will be how much cloud cover we'll see. Model soundings continue to look rather pessimistic here with low-level moisture trapped below an inversion around 850 mb. If that pans out, another day in the upper 60s to around 70 can be expected. For now, have blended the guidance to a 50/50 HREF/NBM blend with highs around 70 in the northeast with a warmer gradient out in the I-65 corridor and points west with low-mid 70s. By Thursday night, we'll start to eventually mix out the inversion aloft which should allow skies to clear a bit more. Overnight lows will likely exhibit a gradient with low 50s over the Bluegrass region and mid-upper 50s in the I-65 corridor and points west.

LONG TERM /FRIDAY THROUGH TUESDAY/

Issued at 314 AM EDT Wed Sep 23 2026

Friday through Tuesday...

Moving into the late week, the upper flow across the eastern CONUS will remain blocking with a strong ridge building from the lower MS Valley northward into the western Great Lakes while a deep upper level low will be found over the NE US. We should see much drier air working into the region with some building heights coming in from the west. With partly to mostly sunny skies expected, we'll see temperatures moderate a bit. The coolest readings will be in the northeast/Bluegrass region with lower 70s, but mid-upper 70s will be found in the I-65 corridor and back into western KY. Clear skies and light winds will allow good radiational cooling to occur Friday night and Saturday morning with lows dropping into the lower- mid 40s over the Bluegrass with mid-upper 40s in the I-65 corridor and western KY.

Ridging will continue to build across the region for Saturday resulting in a beautiful fall day with a decent amount of sunshine and highs topping out in the 73-78 degree range. Lows Saturday night will drop back into the upper 40s/around 50 in the Bluegrass with lower 50s across the I-65 corridor and back toward the I-165 area. Highs on Sunday will be similar to Saturday with perhaps a bit of high cloudiness moving into far western KY. Will go with highs in the 74-79 degree range here with overnight lows in the upper 40s/lower 50s.

For Monday/Tuesday, flow pattern will change slightly across the CONUS with a deep upper and surface low bringing very showery/windy conditions to the NE US while a ridge will be found across the central US. The Ohio Valley will remain in a northerly flow aloft on Monday transitioning to more of a westerly flow by Tuesday. Temperatures should continue to slowly moderate on Monday with highs in the upper 70s east of I-65, and west of I-65, we'll see highs mainly in the lower 80s. Further moderation is expected by Tuesday with highs warming into the lower 80s in the east with mid-upper 80s in the west.

AVIATION /12Z TAFS THROUGH 18Z THURSDAY/

Issued at 651 AM EDT Wed Sep 23 2026

Cool northeast flow will continue across the region today with low clouds remaining socked in. Cigs this morning will be a mix of LIFR/IFR and will eventually rise into the MVFR range by mid-late morning. Scattered showers will be possible this afternoon mainly in the LEX/RGA area. CIGs may return to VFR for a period late this afternoon and into this evening. However, the latest guidance suggests that cigs will build back down tonight with IFR cigs being possible at the terminals.

LMK WATCHES/WARNINGS/ADVISORIES

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