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KEY MESSAGES

* Winter Weather Advisory for counties along and north of I-64 for Saturday afternoon and night as another quick-hitting clipper system brings an additional 1-3 inches of snow.

* Cold Weather Advisory for majority of the region on Sunday as a very cold airmass will move into the region. Forecast lows will be in the single digits and highs on Sunday in the teens and low 20s. Minimum wind chills may bottom out in the 10 below to 10 above zero range.

* Temperatures will slowly moderate Monday afternoon through mid next week.

SHORT TERM /THROUGH SUNDAY/

Issued at 355 PM EST Fri Dec 12 2025

===== Tonight and Tomorrow =====

Temperatures range considerably across the region today, with portions of south-central KY enjoying the mid to upper 40s and sunshine, and our Bluegrass counties remaining closer to the freezing mark. There's been some decent melting today after this morning's clipper system, so there could be some instances of refreezing/black ice on roads overnight as our sfc temps drop back down into the 20s. However, regional traffic cams this afternoon show that roads have mostly dried up since this morning, so the chance seems fairly low and/or isolated.

We'll continue to see dry weather for tonight as our area will be located between two systems. However, another shortwave rotating around the parent upper low over the northern Great Lakes will drive a second cold front through the Midwest and Ohio Valley late in the day tomorrow, which will bring another round of snow to at least the northern portion of the forecast area.

Forcing and moisture will be better to our north, where stretches of IL/IN/OH will be more under the right entrance region of an upper jet, coupled with mid-level FGEN and negative EPV. However, model guidance does extend this favorable forcing and moisture down into southern IN and northern KY, which will support another round of snow for late Saturday afternoon and into Saturday night. Though the best frontogenetical component may not sag south into the I-64 corridor until after 00z, which does agree with our higher PoPs arriving for the evening hours. Current forecast continues with a swath of 1-2 for most counties along and north of the I-64 corridor, with slightly higher amounts possible north of I-71, such as Madison, IN. After collaborating with neighboring offices, a Winter Weather Advisory was issued for counties along and north of I-64 for Saturday night. It is possible that the advisory could end up being a row of counties too far south, as our Probabilistic Precipitation Portal indicates a 34% chance of exceeding 1 inch of snow in Lexington and Frankfort, with better chances the more north you go.

===== Very Cold Temps Follow =====

Any lingering snow will exit our region before sunrise on Sunday, with a very cold, arctic airmass set to crash into the region behind the departing clipper system. We'll see temps tank late Saturday night or early Sunday morning, with lows bottoming out in the single digits across southern IN and north-central KY, where the lingering snowpack will be, and low teens across south-central KY. To make matters worse, NW sfc winds due to a tightened sfc pressure gradient ahead of the strong sfc high will keep winds breezy, which will result in wind chill values to be as low as -10F across southern IN, and at or slightly below 0F across central KY. With high confidence on these impactful temps and wind chills, have added a Cold Weather Advisory headline for Saturday night and into Sunday for a large portion of the forecast area. The only area that may remain above their advisory criteria is the Lake Cumberland area, but this could change in upcoming forecasts.

We remain under strong CAA through Sunday, with temps expected to only reach the teens during the daytime. It will be a brutally cold day, and forecast high temps could end up being near the cold max records for Dec 14 at SDF (15F, 1914) and BWG (21F, 1985).

LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/

Issued at 355 PM EST Fri Dec 12 2025

===== Sunday Night into Early Next Week =====

The upper flow regime will feature deep NW flow by Sunday night and into Monday, with any jet structure well north of our area, and ridging over the northern Mountain West region. Sfc high pressure will be moving directly over the area during Sunday night and into Monday. This will support another night of great radiational cooling conditions as any lingering snow cover will help amplify the cooling process. As such, we expect to see another morning of sfc low temps bottoming out in the single digits, and with the sfc high directly overhead, expect majority of the region to see these single digit temps. However, winds will be much lighter than Sunday morning, which will lead to our wind chills being near the ambient temps. Due to this, less confident in needing a Cold Weather Advisory for Monday morning, but it will still be something to keep tabs on and consider with future forecast packages.

A mid-level shortwave rides through the NW flow across the Great Lakes on Monday, and while the sfc high pressure keeps us dry, a healthy 40-50kt LLJ will sweep across IN, and may clip our northern half of the forecast area. This will influence a WAA take over for us, with some breezy SW sfc winds helping us recover from the single digits earlier in the morning. Forecast temps are expected to peak in the upper 20s to mid-30s. While those temps are still below normal, it'll be a nice recovery after a gelid morning.

We remain dry for Tuesday as sfc high pressure shifts more toward the SE US, and we should finally see temps warm above freezing again during the day.

===== Wednesday - Friday ====

We take on a much milder pattern for the second half of the week, with temps warning into the 50s for Wednesday and Friday, and closer to 60 on Thursday. Additional WAA is expected across the region for Wednesday night, which is when we will find ourselves ahead of an approaching cold front that will be tied to a sfc low well north into Canada. Global models diverge from here, but WPC guidance favors the Euro solution with a line a gusty showers plowing through the area on Thursday. Dewpoints try to get into the low 50s during the day, but sfc temps also remaining in the 50s will help us keep instability potential lower. Shear parameters will be quite high though, given a ripping 850mb jet along or just ahead of the front that could be pushing 70ks. If anything, that jet will really ramp up our moisture transport vector, leading to a high chance for rain showers to pass through.

CAA quickly follows behind the front, with temps possibly dipping down to the freezing mark by Friday morning.

AVIATION /18Z TAFS THROUGH 00Z SUNDAY/

Issued at 1227 PM EST Fri Dec 12 2025

Clearing of the morning cloud deck has resulted in some blue sky and VFR conditions. However, will expect cigs to build back this afternoon, returning the terminals to MVFR for this evening and into the overnight. Otherwise, winds will be swinging around this afternoon as the sfc low slides through the TN Valley, but should become more of a NW component by tonight and tomorrow. MVFR cigs are forecast to continue for tomorrow, with some IFR possible.

LMK WATCHES/WARNINGS/ADVISORIES

KY...Winter Weather Advisory from 1 PM Saturday to 7 AM EST Sunday for KYZ031>037-041>043-049. Cold Weather Advisory from 1 AM EST /midnight CST/ to 1 PM EST /noon CST/ Sunday for KYZ023>043-045>049-053>057-061>067- 070>072. IN...Winter Weather Advisory from 1 PM Saturday to 7 AM EST Sunday for INZ076>079-092. Cold Weather Advisory from 1 AM EST /midnight CST/ to 1 PM EST /noon CST/ Sunday for INZ076>079-083-084-089>092.