textproduct: Louisville

KEY MESSAGES

* Dry weather combines with pleasant temperatures and humidity again today.

* Some spotty 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.

* A round or two of stronger thunderstorms is possible Monday and/or Tuesday, however confidence remains low on the finer details.

SHORT TERM /THROUGH TONIGHT/

Issued at 250 AM EDT Fri Jul 24 2026

Expect another dry day as surface high pressure holds on a bit longer across the area. We'll have an inverted surface trough to our SE that could trigger some convection into the Appalachians. In addition, there will be a shortwave moving into the lower Missouri River Valley that will spark some showers and storms, but overall our CWA should stay sandwiched between these two areas and remain dry. Temperatures will remain below normal for this time of year, however we will see an uptick from the past couple of days. Look for highs in the low 80s for most with dew points still in the more comfortable 55 to 60 degree range.

Later tonight, we will carry some isolated shower or storm chances across our far SW CWA where left over showers from the aforementioned shortwave could move into the area. The rest of the area should continue to be dry through the overnight. Tonight's low temperatures should be notably milder than previous nights given an increase in low level moisture. Look for low and mid 60s for most.

LONG TERM /SATURDAY THROUGH THURSDAY/

Issued at 250 AM EDT Fri Jul 24 2026

This Weekend...

Upper ridging from the western CONUS starts to build more into the central CONUS this weekend with general troughing from the eastern Great Lakes into New England. We'll be situated between these two features with our upper flow orienting to a more NW flow aloft type of setup. At the surface, high pressure will start to lose influence over our area, and a frontal boundary will lift northward toward the TN Valley as a weak warm front. PWAT values will surge up around 2" through the column as we get into Saturday, and again on Sunday. In addition, instability will build into our area the second half of the weekend as the eastern periphery of the upper ridge gets more established across the central CONUS into the mid Mississippi River Valley. Overall, deep layer shear on Saturday isn't overly impressive, at least in the lower levels. Above 500 mb, we will have the exit region of a notable mid to upper level impulse, however H85 winds are more likely to be 10 knots or less. Regardless of the shear profile, the environment looks mostly capped, so only expect some isolated to widely scattered shower chances below the inversion for Friday night into Saturday mainly across southern and western KY.

By Sunday, overall, deep layer shear profiles should improve some, but will still be fairly weak below 500 mb. Forecast soundings look less capped by this time, and suggest that some strong instability on the order of 3000-4000 J/KG of CAPE could develop. It is possible some strong to severe storms could develop on this day, however most of the deterministic data doesn't have much of a trigger to key in on. Will keep an optimistic forecast going for now given that lack of a confident trigger, and focus more on the building heat and humidity for this time. Forecast highs are expected to surge back into the upper 80s and around 90 assuming we stay mostly dry. In addition, dew points are expected to recover to the low and mid 70s for most of the CWA (minus the Bluegrass counties). This could put max afternoon heat indices back in the 95 to 100 degree range along and west of I-65.

Early Monday - Late Tuesday...

Our NW flow aloft pattern will hold over the area through at least the middle of next week with strong upper ridging dominating the western and central CONUS, and troughing over the eastern Great Lakes and New England. We'll likely keep plenty of instability across our area thanks to the eastern periphery of the upper ridge. In addition, deep layer shear will be somewhat enhanced by the mid to upper level jet structure nosing SE into our region. Models continue to hint at a shortwave or two embedded in the NW flow aloft upstream of us in the early Monday through late Tuesday time frame, and these could be a trigger for some MCS activity upstream of us that could potentially forward propagate into our area. The overall pattern does have that look, but overall the run to run data has been consistently inconsistent with any key features. We'll have to keep an eye on the Monday/Tuesday time frame for potential MCS activity riding into our area between the mean 700-300 mb flow and NNW to SSE oriented instability gradients. It is possible the bulk of any MCS activity stays to our north and east, but it is also plausible to get a forward propagating/cold pool enhanced complex to work into our area from the north. We'll keep monitoring, especially across our NE CWA where most of the activity should track if it occurs. Wouldn't be surprised to see an eventual outlook over our area, particularly for the Monday time frame.

For now, the bigger story will be the heat and humidity with Mon/Tue high temperatures expected to reach the lower 90s combined with low and mid 70s dew points across much of the area. Along and west of I- 65 our max HI values could reach the 105+ range, and some Heat Advisory headlines appear possible for these two days. One caveat would be if we do get MCS activity to wreck the temp forecast either of these days.

Wednesday - Thursday...

Actually have higher confidence in the mid week outlook as the upper pattern should remain the same. However, data agrees that the NW flow aloft will be more void of any notable triggers, and surface high pressure builds back into the area behind a passing cool front or convectively reinforced cold pool from the early week concerns. Looking for a drier and slightly cooler forecast as highs return back to the upper 80s to near 90.

AVIATION /18Z TAFS THROUGH 00Z SUNDAY/

Issued at 118 PM EDT Fri Jul 24 2026

VFR weather continues this afternoon and evening, though with increasing mid and upper level cloud cover. Winds are expected to go nearly calm overnight, and a weak disturbance could bring -SHRA to BWG early tomorrow morning. All other terminals are expected to remain dry, and overall VFR is expected through tomorrow as well. Winds will swing around from the south tomorrow, but should remain rather light.

LMK WATCHES/WARNINGS/ADVISORIES

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