textproduct: Louisville

KEY MESSAGES

* Scattered storms continue this afternoon and evening bringing heavy downpours, lightning, and potentially damaging wind gusts.

* Rainfall totals of 0.25-0.75" from widespread storms this afternoon are expected with localized 3+" possible, bringing a localized flash flooding threat.

* A line of storms bringing potentially damaging wind gusts especially across eastern-southern IN moves in Saturday evening around 9 PM that will slow down and weaken across central KY overnight into Sunday.

* There is a chance for stronger storms on Tuesday evening and into Tuesday night. Monitor the forecast as more details become clear.

SHORT TERM /THROUGH SATURDAY NIGHT/

Issued at 337 PM EDT Fri Jul 17 2026

Temperatures have peaked in the upper 80s and brushing 90s this afternoon. With convective temperatures in the upper 80s and towering Cu, scattered showers and storms have developed over the region. With MLCAPE 2000-2500 J/kg and PWATS of 2-2.2 inches, storms are robust allowing for heavy rainfall and gusty winds. HREF LPMMs are showing localized areas of 2-3 inches of rainfall. Localized flooding will be possible this afternoon and evening. These conditions will continue through the remainder of the afternoon and into the evening.

As the sun sets this evening, instability will wane and storms will dissipate. Overnight, calm to light winds and mostly clear skies will help temperatures to cool into the low to mid 70s. Patchy fog will be possible in the early morning hours, especially over areas that saw rainfall from this afternoon.

On Saturday, troughing will move through the Ohio Valley and send a cold front south. Ahead of this cold front, temperatures will increase into the upper 80s and brushing 90F in the afternoon. PWATs will remain between 2 and 2.2 inches, which is in the 99th percentile of climatology. Given these conditions, isolated to scattered showers and storms may develop in the afternoon. These will be pulse-like, where the main hazards will be heavy rainfall and gusty winds.

The cold front will approach the region in the late evening and into the Saturday night period. A line of storms is expected to accompany the cold front. There will be a weakening shear gradient as the line moves south through the region. Additionally, CAPE will wane overnight. Due to these conditions, the line of storms is expected to be weakening as it moves into and through the area. Strong winds and brief, heavy rainfall will be possible over southern Indiana and northern Kentucky between 9PM EDT and 3AM EDT. As the storms approach southern Kentucky, the severe threat will be quite limited.

LONG TERM /SUNDAY THROUGH FRIDAY/

Issued at 337 PM EDT Fri Jul 17 2026

The cold front is expected to stall over central/northern Kentucky on Sunday. Continued moisture and warmth to the south of the front will allow for another chance for showers and storms Sunday afternoon and evening. Main hazards will be gusty winds and heavy rainfall.

North of the cold front, we will see a reprieve from the heat with temperatures in the mid 80s and dew points in the upper 60s.

On Monday, the front will lift northeast as a warm front. This will allow moisture and temperatures to increase over the region. Temperatures will return to the upper 80s and brushing 90s and dew points in the low to mid 70s. This will put heat indices in the upper 90s and low 100s. A few isolated showers and storms will be possible, remaining pulse-y.

The next more impressive system will move through on Tuesday. A strong upper low will move through the northern Great Lakes and will send a cold front south. A strong line of storms is expected to move through the region. EFI CAPE/Shear is showing a decent signal for this time of year, which indicates a strong environment for severe weather. Current timing will be Tuesday evening and into the overnight period.

Otherwise, Tuesday will be quite warm as southerly flow continues to pump moisture into the region. Heat indices will approach Heat Advisory criteria around 105F.

Wednesday through the end of the week, high pressure will move into the region and we will see drier and more mild conditions.

AVIATION /18Z TAFS THROUGH 00Z SUNDAY/

Issued at 139 PM EDT Fri Jul 17 2026

TCU has formed over the region and scattered showers and storms are present over the entire area. These showers and storms will continue through the remainder of the afternoon and into the evening hours. As the sun sets and instability wanes, showers and storms will dissipate. In storms, rain will become heavy and lightning may be frequent. Individual pulse storms will form and dissipate within 30- 40 minutes. Overnight, winds will become calm to light. Fog formation is possible. On Saturday, winds will pick up out of the west around 8-11kts and gusting up to 22kts.

LMK WATCHES/WARNINGS/ADVISORIES

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