textproduct: Louisville

KEY MESSAGES

* Dry weather combines with pleasant temperatures and humidity through late week.

* Shower and storm chances return heading into the weekend, and heat and humidity return late weekend into early next week. Max afternoon heat indices could be in the triple digits for some by early next week.

SHORT TERM /THROUGH FRIDAY NIGHT/

Issued at 318 PM EDT Thu Jul 23 2026

It is a very pleasant day across the region, especially for late July. The KY Mesonet network shows temps in the upper 70s across the entire state, with some fair weather diurnal cu popping up on GOES satellite. Expect these clouds to dissipate this evening as peak heating is lost. Dry weather continues as sfc high pressure remains across the area, with a cool overnight expected with lows in the upper 50s and lower 60s.

Another dry day tomorrow, though with temps slightly warmer with highs in the low to mid 80s. Low end precip chances eventually make a return in our southwest by Friday night as the sfc boundary begins lift north and the sfc high departs. Model soundings do not look too concerning, with limited instability and stable low levels. There also may be some decent dry air below 850mb that could erode some of the shower activity through early Saturday morning.

LONG TERM /SATURDAY THROUGH THURSDAY/

Issued at 318 PM EDT Thu Jul 23 2026

===== This Weekend =====

A large dome of high pressure will reside over the western US the begin the weekend, however that will lead to lingering downstream troughing across the eastern US. This places the Ohio Valley in a deeper NW flow aloft between these two features. Sfc high pressure will have shifted toward the East Coast by this time, which will open the door for precip activity to return, especially for Saturday as a stalled sfc boundary across the TN Valley begins to lift back to the north. Model soundings do not indicate a lot of CAPE or shear on Saturday, though PWATs near 2 inches will support some efficient rainfall at times. The best flow in the column likely remains at the mid-levels or higher, so there likely won't be much low-level steering flow. As such, mainly looking at pulse convection on Saturday afternoon, mainly in the I-165 (Natcher Pkwy) area and southwestward, though still could see some pop up storms across southern IN and central KY west of I-75. That boundary will continue to sit just to our southwest on Sunday, and could be the focus for additional shower and storm activity. Should see more instability on Sunday, though weak shear is expected to continue. Confidence remains lower on Sunday as models continue to vary on convection initiation.

Temps will be heating back up over the weekend, with Sunday being the hotter day. Saturday will feature temps in the low to mid-80s, though Sunday brings a return to the 90s. Dewpoints will be creeping back up into the 70s, and which could yield heat indices near 100 by Sunday.

===== Next Week =====

We'll remain situated in the NW flow aloft for next week as the strong upper ridging holds over the western US. Temperatures and humidity continue to increase next week, with daily highs in the 90s, and afternoon heat indices near 100F possible Monday and Tuesday. That will also support increasing destabilization across the Ohio Valley, which combined with the NW flow, could set up additional severe threats with upstream MCS activity rides down the NW flow and/or CAPE gradients and into the Ohio Valley. SPC already has a 15% risk for Monday, which will need to be watched closely. As mentioned in the prior discussion, our N/NE portion of the forecast area has the best chance for severe activity next week for now, but that obviously could change.

As mentioned above, heat indices near 100 are expected next week, which could be borderline heat advisory if we see a few continuous days of heat. This still remains somewhat lower confidence as well though, because any MCS or thunderstorm threat could knock down the heat in the afternoon.

AVIATION /18Z TAFS THROUGH 00Z SATURDAY/

Issued at 106 PM EDT Thu Jul 23 2026

VFR conditions continue through the TAF period as high pressure remains across the region. Generally light winds are expected, and additional SCT cu through the afternoon. Mostly clear and VFR expected tonight.

LMK WATCHES/WARNINGS/ADVISORIES

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