textproduct: Louisville

KEY MESSAGES

* Showers and thunderstorms capable of producing heavy rainfall and localized gusty winds will be ongoing for the start of the day today before dissipating later this morning. Locally 1-2+ inches of heavy rainfall is possible this morning leading to flash flooding concerns.

* Another round of storms is likely (50-80% chance) Saturday evening through Saturday night. These storms will also pose a risk for severe weather and excessive rainfall leading to potential flash flooding.

* Typical summertime temperatures with daily chances for isolated/scattered afternoon showers and storms is favored for much of next week.

SHORT TERM /THROUGH TONIGHT/

Issued at 218 AM EDT Sat Jul 11 2026

The main concern remains hydro and the potential for flash flooding. With a secondary concern for strong to severe due to gusty and potentially localized damaging winds from downburst. The hi-res convective allowing models (CAMS) have struggled at times tonight with placement and timing of ongoing convection coming out of IL, MO and western KY. At times their placement of QPF and convection have been too far north which is a known issue with CAMS. With that in mind we have turned to looking at both the 6hr and 24hr LPMM (Localized Probability Match-Mean) from the HREF Ens. and the NBM 6hr and 24hr probability of 2+ inches to get an idea on where and when we could see the highest rainfall amounts. There have been two distinct areas of concern emerging from this data with one being across our far southwest corner of the CWA around Ohio, Butler, Logan, Simpson, Warren, Barren and Allen counties. The other has been to the north coming out of southern IN into north central KY from Louisville to Elizabethtown over to Lexington. In these areas the LPMM highlights narrow swaths of 1-2 inches with localized pockets of 3-4+ inches over the next 24 hours. This lines up very well with the NBM 2"+ probability of 40-60% adding confidence to the current forecast.

This first wave of thunderstorms and heavy rainfall will work through the CWA now through around 12-14z with some of the heaviest and training bands of heavy rainfall from Jasper IN developing along a boundary near Louisville to Elizabethtown to Somerset, KY. The other area will be across Warren, Ohio, Butler, Logan, Simpson Allen counties where we could see prolonged heavy rainfall and thunderstorms. Some of this convection has had a history of 1-2 inches/hour rainfall rate with localized higher amounts and flash flooding. While the severe threat is generally low, these storms could also produce gusty and localized damaging wind gusts approaching severe criteria (58 mph).

Once this wave passes and moves out later this morning, like we've seen over the last couple of days, a lull in activity is likely for a couple of hours through the morning into the early afternoon. Models begin to ramp up convection development later in the afternoon and evening as the sfc boundary across central IN starts to drift southward towards southern IN and the Ohio River and a weak mid/upper level impulse works into the Ohio Valley. Those features combined with the atmosphere destabilizing due to daytime heating, we will get another round of showers and thunderstorms capable of heavy rainfall and potentially strong storms. SPC will place the far southwest corner of the CWA into a Slight Risk (level 2 of 5) and the rest of the CWA in a Marginal (level 1 of 5) for severe storms later today. Like it has been the last couple of days, localized gusty straight-line winds will be the main threat with any storms that form. PWAT values once again approach 2.00"+ with model soundings showing "tall skinny" CAPE profiles continuing the on going flash flood threat.

The boundary and the upper level low will keep the activity going into the evening and potentially again during the overnight hours tonight into early Sunday morning. Currently the Flood Watch remains in effect until late tonight or 6z Sunday.

LONG TERM /SUNDAY THROUGH FRIDAY/

Issued at 218 AM EDT Sat Jul 11 2026

***** SUNDAY AND MONDAY ***** Strong upper ridging to our west will try to build and expand eastward from the Dakotas and Upper Midwest into the Great Lakes Sunday into Monday. Lingering upper/mid level energy from Saturday will retrograde back to west in the form of a weak cutoff low and be slow to work across the TN valley. At the sfc, high pressure over the Great Lakes will try to push southward towards the Ohio Valley and push the quasi-stationary boundary southward into TN on Sunday. While we don't expect to be as wet as we were Thursday through Sunday, lingering moisture over the area (PWAT values generally around 1.5") will be enough to keep shower and thunderstorm chances around as we go into the start of the week. Temperatures will be a bit cooler than seasonal normals with highs in the low/mid 80s and lows in the mid/upper 60s.

***** TUESDAY AND WEDNESDAY *****

Upper low is expected to work westward into the central CONUS sometime midweek as sfc high pressure continues to build in from the north. There remains some timing and placement discrepancies in the deterministic guidance when it comes to the upper disturbance and how fast it exits the region. The slower solution keeps our weather a little unsettled with daily afternoon shower and storm chances will the faster solution is a little drier for the middle of the week. If storms are able to develop each afternoon, weak flow aloft should lead to mainly garden-variety, slow moving summer storms with minimal severe potential. Given the likely slow movement of storms, a lingering heavy rainfall/flooding threat can't be ruled out, though limited coverage of storms should limit this threat. Temperatures start to warm to near summer-time normals in the upper 80s to near 90 and lows in the upper 60s to low 70s.

***** THURSDAY INTO NEXT WEEKEND *****

A more substantial upper trough is progged to descend across the eastern part of North America. Medium-range guidance still features quite a bit of spread as to how much this feature will be able to push the upper ridge back to the west, which will impact the forecast for late next week into the following weekend. If the trough is able to dig more to the south/west, it would bring a front down into the Ohio Valley that would increase storm chances/coverage Thursday into Friday. However, a more resilient upper ridge would support warmer and drier weather over the same period.

AVIATION /06Z TAFS THROUGH 12Z SUNDAY/

Issued at 137 AM EDT Sat Jul 11 2026

A widespread area of rain with some embedded thunderstorms are currently making its way in from the west. MVFR conditions are expected with these storms and areas of heavy rain. Ceilings will begin to lower with the system bordering MVFR with a secondary layer below 3kft. A brief dry period is forecasted for early afternoon when clouds will return BKN/OVC100 before another wave of showers and storms move in by tonight.

LMK WATCHES/WARNINGS/ADVISORIES

KY...Flood Watch through late tonight for KYZ023>043-045>049- 053>057-061>067-070>078-081-082. IN...Flood Watch through late tonight for INZ076>079-083-084- 089>092.