textproduct: Louisville

KEY MESSAGES

* Up and down temperatures expected this weekend as a dry cold front moves through the region tonight.

* Off and on chances for light rain showers are expected Monday afternoon through Wednesday, though a washout is unlikely.

* Unseasonably warm temperatures are likely around Christmas, with highs in the 60s to around 70 likely from Christmas Eve through Friday.

SHORT TERM /THROUGH SUNDAY NIGHT/

Issued at 251 PM EST Sat Dec 20 2025

Quiet weather expected to continue through the end of this weekend, however a couple of highlights worth noting. We'll continue to gust out of the SSW to NNE across the area ahead of an approaching cold front. Most gusts should range between 20 and 25 mph, along with an impressive dry air mix down event ongoing. The "dry" cold front is set for passage between around 7 or 8 PM EST to around 1 or 2 AM EST. Not expecting any precipitation with this feature, however will likely see at least some increase in sky cover.

High pressure takes hold for tomorrow with continued dry conditions and considerably cooler temperatures. After morning lows in the upper 20s and low 30s for most, Sunday highs only recover to the low 40s north, and mid to upper 40s south.

LONG TERM /MONDAY THROUGH FRIDAY/

Issued at 251 PM EST Sat Dec 20 2025

Monday - Tuesday Night...

Surface high pressure loses influence over our area through Monday as it shifts off the mid Atlantic Coast. Meanwhile, a decent pressure gradient sets up between that feature and cyclogenesis over the central Plains. From a temperature standpoint, the resulting steady warm advection allows for a nice recovery from morning lows mostly in the 25 to 30 degree range, to Monday afternoon highs in the low and mid 50s. The morning will start out dry, however increasing clouds and light rain chances arrive for the afternoon thanks to some isentropic lift on a 30-40 knot low level jet and an approaching cold front. These chances will mainly be along and west of I-65 through the daylight hours, then giving way to likely chances overnight across the entire county warning area with the LLJ better established over the area by then.

The progression of things into Tuesday will be rather interesting as upper ridging amplifies over the southern CONUS, and the surface cold front trailing from an eastern Canada surface low becomes more parallel to the upper flow over our region. This results in the boundary stalling out either near or close to our area, and will keep light rainfall chances lingering through at least Tuesday night. It is possible our northern CWA drys out by this time as surface high pressure centered over the Great Lakes tries to build in behind the front. In other words, the best chances for light rain Tuesday night will be across southern KY.

Christmas Eve - Christmas Day...

There is less certainty in light rainfall chances for Christmas Eve through Christmas Day as the weak frontal boundary over or near our area washes out. Overall will keep chances pretty small here and through Christmas night as models show a shortwave passing through the progressive NW flow aloft. Overall confidence is low in much, if any, rainfall from either of these features. Even if it does rain, it will likely be light and not an all day thing. On the flip side, have very high confidence in mild temperatures as the upper ridge across the southern CONUS becomes a bit more established over the area. Christmas Eve highs in the upper 50s and low 60s likely give way to Christmas Day highs in the 65 to around 70 degree mark. From a temperature standpoint, definitely will be more like a "Mele Kalikimaka" type of Christmas than a "I'm Dreaming of a White Christmas". Keep dreaming for next year I suppose. Will note that there is a lot of mention of lingering and small rain chances from early through mid week, but overall QPF totals through that time look very light and likely less than a quarter inch for most.

Friday - Saturday...

Medium confidence for the late week into weekend time frame as a slightly stronger shortwave progresses through the zonal flow aloft and the upper ridge anchored over the southern CONUS breaks down a bit. The associated surface low looks to pass through the Great Lakes region on Friday with mild temperatures once again across our area in the mid to upper 60s. Rain chances will also accompany this feature, and ahead of the approaching cold front. That front passes later Friday with a dry and slightly cooler Saturday expected.

AVIATION /18Z TAFS THROUGH 00Z MONDAY/

Issued at 1242 PM EST Sat Dec 20 2025

Pretty quiet TAF period in store, despite a cold frontal boundary moving through and some brief LLWS concern this evening at LEX/RGA. Look for VFR conditions through the TAF period with only some SCT high clouds to speak of today. Steady SSW winds between 10 and 15 mph will occur, with occasional gusts mostly in the 20 to 25 mph range.

Winds slacken early this evening, and veer to a SW, then W, and NW component late evening into the overnight as a dry cold front passes through the area. Will see a brief uptick in Sct-Bkn mid level clouds 4-5 k feet from early evening through late evening. Then, look for a return to upper sky cover. Sunday morning brings Sct-Bkn upper sky cover with a light N to NNE wind. Brief LLWS threat ends at LEX/RGA by late evening.

LMK WATCHES/WARNINGS/ADVISORIES

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