textproduct: Louisville

KEY MESSAGES

* Slow moving cold front will bring widespread rain showers to the region through tonight. Additional rounds of showers are possible across southern Kentucky on Saturday and Sunday.

* Overall rainfall amounts are expected to be .5" to 1" for most, however isolated amounts around 1.5" are possible, especially across southern In and/or northern KY.

* Dry weather will return to the region by Sunday afternoon with much of next week remaining dry. Temperatures next week will be seasonal with large diurnal temperature ranges. Some spots across southern Indiana and northern Kentucky will see overnight drop into the upper 30s/low 40s Tuesday and Wednesday morning.

DISCUSSION

Issued at 300 AM EDT Fri Oct 2 2026

Water vapor imagery shows an impressive fetch of moisture stretching through Mexico, up through the the mid Mississippi River Valley, and then up trough New England. This moisture axis is oriented roughly parallel to a surface cold frontal boundary and along the mid and upper jet axis over our area. Given good upper level divergence and a responding low level jet beneath it, there is plenty of lift through the atmospheric column combined with deep moisture pushing PWATs over 2". The end result will be widespread rainfall today with perhaps a few pockets of embedded thunderstorms. Overall mid level lapse rates are expected to remain poor today combined with meager ML CAPE values likely 500 J/KG or less. Ultimately, heavy cloud cover and a steady NW/N wind behind the frontal passage will limit the potential to destabilize, and the potential for any stronger storms.

Overall rainfall amounts are expected to mostly be in the .5" to 1" range across the area, although a few pockets of amounts around 1.5" are possible especially along and north of I-64 where the most residence time is expected. There will be quite a temperature gradient from NW to SE across the area today with areas north of the cold frontal boundary only reaching the low and mid 70s. SE of the boundary, look for highs in the low and mid 80s. This line should stretch from roughly Bowling Green, KY up through Winchester, KY.

The surface boundary stalls across our far SE CWA later tonight into Saturday with a few lingering showers along the KY/TN border and through the Lake Cumberland region. These chances will basically linger until a shortwave trough axis finally pushes through later Saturday into Sunday morning. Outside of the scattered shower chances down south through the first part of the weekend, the rest of the CWA will be dry as Canadian surface high pressure gets more established over southern Indiana and north central KY. Looking for highs on Saturday in the upper 60s and low 70s across the area under a steady NE surface wind. Overnight lows will be chilly in the upper 40s and 50s across the area.

Sunday, we sit in the right entrance region of the UL jet streak. This should provide decent lift; combined with our lingering surface cold front, expect some lingering sprinkles to showers in the Lake Cumberland area. Post-frontal highs should be around the 75 degree mark, with Bowling Green and the southern part of the region perhaps pushing 80 if cloud cover clears quickly enough to allow surface heating. Showers should fully leave the area by Monday morning, and overnight lows are in the upper 40s and low 50s. Southern Indiana and Ohio Valley should clear out clouds by Sunday afternoon while the Bowling Green/Lake Cumberland takes until at least Monday morning to reach fully clear skies with dry air at 850mb. Monday should bring highs around 70 for S IN/Ohio Valley and 75 for S KY. Should be breezy with sustained northeasterly winds around 10 mph and gusts up to 18 mph possible. Overnight lows should be in the low to mid 40s. Frost is doubtful for this week, but probably not far away.

Tuesday through Thursday, the surface High swings across the Great Lakes, stalling out the cold sfc front south of our CWA - this should lead to light easterly/northeasterly flow at the surface. The UL ridge over the Great Plains should weaken enough to lead to solid W to E flow aloft. We mix a bit of moisture back in, leading us to push up to highs in he upper 70s and potentially breaking 80 on Thursday and Friday for Bowling Green and the Louisville metro. Lows should remain in the upper 40s and low 50s.

AVIATION /06Z TAFS THROUGH 12Z SATURDAY/

Issued at 203 AM EDT Fri Oct 2 2026

VFR conditions will continue the first part of the day, with sustained southerlies around 10kts for the area. Current TAFs include brief LLWS for LEX and SDF due to a strong inversion, with sfc winds southerly and winds around 1500/2000 ft SW at 35-40 kts. This afternoon into evening, a cold front and showers roll through, drastically changing the wind direction (50+ degrees/hour around 11- 12z) sustained around 12-15 kts and gusts of 20 possible. Ceilings will drop rather quickly this evening with approaching showers. A rumble of thunder can't be ruled out, but areal coverage and confidence are both low. HNB should begin SHRA in the next hours, reach SDF and BWG around 11z, and LEX/RGA around 14z. Evening should mean IFR and LIFR CIGS, but should move through for HNB around 20z, SDF at 23z, LEX/RGA/BWG at 06z on the 3rd.

LMK WATCHES/WARNINGS/ADVISORIES

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