textproduct: Louisville

KEY MESSAGES

* If sufficient clearing occurs, hot and humid conditions are expected Today and again Thursday. Peak afternoon heat indices of 95-105 degrees are possible each afternoon.

* An approaching cold front later in the week provide more opportunity for rain and some storms late Thursday evening through Friday, though timing is still uncertain.

* After a dry Saturday, an unsettled and overall cooler pattern takes hold for late weekend into early next week.

UPDATE

Issued at 555 AM EDT Wed Jun 10 2026

The MCV associated with last evening's thunderstorm complex over central Indiana has now pushed into far southern Ohio, and given the lack of any outflow from the weak showers and storms near the Bluegrass, really don't anticipate much more shower and storm development over our area. Low level jetting is expected to weaken over the next 3 hours, further contributing to the closing window for any showers and storms. The Flood threat is ending, and will cancel the rest of the Flood Watch for our area as a result.

SHORT TERM /THROUGH TONIGHT/

Issued at 249 AM EDT Wed Jun 10 2026

Things have been quiet through the overnight so far as the backbuilding MCS offered consistently by the CAMs has yet to materialize. We aren't out of the woods yet as a few isolated showers have recently developed over our NE CWA. That being said, the ingredients for development earlier this evening were supposed to be from the subtle 30 knot W-E low level jet converging with outflow from the MCS that developed over central IN earlier this evening. Given that this has been occurring for several hours, and that the low level jet isn't getting any stronger do think the window is closing for development. Plus, the convective complex is mostly weakened so you really don't have the strong outflow anymore either. Have trimmed off the western parts of the Flood Watch, and will consider more trimming over the coming hours as the window diminishes. Don't want to be too hasty though given how much rain fell today, and quick redevelopment could lead to a renewed Flash Flood threat pretty quick. Will cautiously trim the Flood Watch until we are certain convective chances have diminished. Did trim the Pops back to the NE considerably to account for current trends.

If storms do redevelop, then the potential for heavy rainfall still exists. PWATs will range between 1.75" - 2" through the column combined with moderate instability and somewhat slow storm movement. Any backbuilding against the subtle low level jet would create additional Flash Flood potential.

Outside of that, a progressive shortwave ridge axis is expected to build into the area today with dry conditions taking hold thanks to the more subsident airmass. Notable heat and humidity will also accompany this drying trend with steady SW winds and partly sunny skies contributing. Looking for max temps in the upper 80s and low 90s, along with low to mid 70 dew point readings. This should yield peak afternoon heat indices in the 100 to 105 degree range across the western two-thirds of the CWA. Farther east, upper 90s to near 100 degree peak indices are expected. In collaboration with surrounding offices have decided not to go with a Heat Advisory, and instead message with a Special Weather Statement and graphics. There is some uncertainty with how well temps will do today with all the rainfall yesterday, and whether or not this convective complex still develops are too factors limiting confidence.

LONG TERM /THURSDAY THROUGH TUESDAY/

Issued at 249 AM EDT Wed Jun 10 2026

Thursday - Friday Night...

Brief upper ridging tries to build in Thursday ahead of a progressing north central CONUS trough. We'll be mostly dry and continued hot and humid under this setup. Looking for highs a degree or two on either side of 90, and with dew points in the low and mid 70s this will yield max heat indices once again in the upper 90s and low 100s for most. Possible Heat Advisory headline needed here, at least for western portions of the CWA as some spots could top out around 105.

May have to carry a small chance of a shower or storm across the northern third of the CWA where moderate instability will develop. However, won't be much in the way of a trigger and there will be at least some bit of a subsidence inversion around 700 mb associated with the upper ridge to overcome.

By Thursday night, we'll focus our attention upstream as a linear MCS could be approaching ahead of the trough mentioned above and its associated cold front. Some of the data has this developing a pretty good cold pool upstream, however it will likely weaken as it approaches our area due to the diurnal minimum, and surging into the less favorable airmass (drier and more stable) from the retreating upper ridge axis. Like the Marginal Risk offered by SPC across our north for whatever wind is left over from the cold pool push if the upstream system is indeed strong. Friday will see the remnants of the weakening system pushing south through our area, along with the associated cold front. Expecting a drying trend from N to S through the day as this progression occurs. This will bring some relief from the previous days' heat and humidity as temperatures fall back into the mid 80s for highs, and lows in the low to mid 60s for Friday Night.

Saturday - Sunday Night...

High confidence in a dry Saturday as high pressure at the surface controls our area behind the cold front, and the zonal upper pattern yields no remarkable features. These dry conditions aren't expected to last long as another frontal boundary slides into our area later Saturday night into Sunday, and will start to stall as it orients nearly parallel to the upper flow. We'll have to watch this setup as a few embedded shortwaves drawing on Gulf moisture could ride along this quasi-stationary boundary into our area, and bring more heavy rain potential on Sunday. Beyond that, uncertainty grows and confidence decreases on whether the boundary stays parked over or near our region, or weather it pushes south and allows for a drier stretch going into early next week.

Monday - Wednesday...

Lower confidence for this time frame with the fine details, but there is decent support for a cooler than normal stretch as broad troughing envelopes much of the central CONUS. This will likely pushed the stalled front boundary through our area by early to mid week, but embedded shortwaves within the parent trough will still keep some shower and storm chances in the forecast through Wednesday. Highs are expected to mostly be in the upper 70s and low 80s during this time, with comfortable lows in the low and mid 60s.

AVIATION /12Z TAFS THROUGH 18Z THURSDAY/

Issued at 644 AM EDT Wed Jun 10 2026

Expect VFR to prevail through this TAF cycle as high pressure builds into the area. The threat for showers and storms is quickly ending this morning near LEX/RGA, and will start them off optimistic and dry. It's possible there could be a brief period of MVFR ceilings at LEX/RGA until late morning, but not enough confidence to carry for now. Otherwise, expect a steady SSW-SW wind around 10 mph through the day. Occasional gusts up around 20 mph are also expected through the afternoon hours, before diminishing this evening. Look for scattered to broken stratocu to develop by late morning thanks to the ample low level moisture, however any ceilings should prevail on the VFR side of the threshold.

LMK WATCHES/WARNINGS/ADVISORIES

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