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KEY MESSAGES

* Dry and very cold tonight into tomorrow. Wind chills in the single digits and below zero tonight and in the teens and 20s tommorow.

* Light rain and snow possible Wednesday and Wednesday night.

* Potentially impactful winter system possible for the weekend, Snow accumulations possible this weekend, but forecast confidence in amounts and timing continue to remains low.

SHORT TERM /THROUGH TUESDAY/

Issued at 345 PM EST Mon Jan 19 2026

Cold air continues to advect in this afternoon and will be in place overnight into tomorrow morning. Sfc high pressure located over KS/MO will continue to build eastward and be over the TN/OH Valleys by tomorrow morning. Temperatures range from the low/mid 20s along and north of the Ohio River into the Bluegrass while we have low 30s further east and south. Winds continue to gust between 20-30 mph resulting in wind chill values feeling like they are in the low/mid teens to low 20s. As high pressure builds in overnight, skies will remain mainly clear and winds will start to become lighter. This will result in very cold overnight temperatures in the single digits for most with more urban areas around 10 degrees. We could have enough of a breeze over the Bluegrass and southeast IN where wind chill values drop to around or even below 5 below zero, with that in mind, decided to keep the Cold Air Advisory in place until 10am EST with no changes to the coverage of the advisory.

With high pressure overhead and a very cold start to the day tomorrow, it will remain cold for the afternoon. While it will be slightly warmer tomorrow than it was during the day today. Afternoon temperatures will only climb to near or slightly above 30. Even with winds expected to be lighter, wind chill values will still be in the 20s with a few spots feeling like the teens.

LONG TERM /TUESDAY NIGHT THROUGH MONDAY/

Issued at 345 PM EST Mon Jan 19 2026

TUES NIGHT - FRIDAY...

Our next chance at precipitation is associated with a quick-moving shortwave trough moving through the Dakotas as it develops a weak sfc low over the central Plains Tues. Night into Wednesday. This system will quickly track into the Great Lakes by Wednesday morning and off into eastern Canada by Wednesday night. Sfc high pressure that kept dry and chilly for the start of the week will work east and be off the Mid-Atlantic coast for the start of Wednesday. Increased SW flow between these to systems will advect in warmer air along with narrow plume of moisture ahead of the associated cold front. Initially, any precipitation Wednesday morning will have to overcome some very dry air near the surface. QPF values remain very light with little to no impacts from any wintry precipitation. Temperatures will also be warmer climbing into the low/mid 40s Wednesday afternoon before falling below freezing Wednesday night into Thursday morning. Another area of high pressure is expected to build in for Thursday with a return of cool, dry weather.

POTENTIAL IMPACTFUL WINTER STORM THIS WEEKEND (SAT-SUN)...

The main focus in the long term is the development of a potential impactful winter system for the weekend.

WHAT WE KNOW... We continue to see a consistent signal in the deterministic models showing a strong sfc high associated with a very cold arctic airmass coming out of Canada interacting with an upper trough associated with the southern branch of the jet stream coming out of Texas, that will lift Gulf Moisture northward over the colder air creating widespread, impactful winter precipitation across the southern US stretching from TX/OK/AR through the Deep South, into the TN & OH Valleys and then into the Mid-Atlantic by the end of the weekend. Strong mid/upper level jet max over the Ohio & TN Valleys Saturday night looks to be the main focus for lift over the area with a lack of sfc low development. The Winter Storm Severity Index probability for Minor Impacts has increased from 40- 60% to most of the state and area at 60% and the probability of Major Impacts climbing to between 30-40 percent by Sunday morning. While confidence is there that a winter system will form and have significant impacts across the southern US for the weekend, confidence is much lower when it comes to the finer details over our area.

WHAT WE DON'T KNOW... While the deterministic are consistent on a winter system taking shape over the weekend, it is very far apart on when it comes to where, when and precipitation amounts. The 12z GFS continues to side on stronger sfc high and drier air winning out to the north suppressing the bulk of the precipitation across TN just up to the KY/TN border. The ECMWF, is further north with the precipitation shield, and also a bit slower with the trough and jet max late Saturday into Sunday. If you are a snow lover, this has more favorable heavy snow track through the CWA and placement of the left exit region of the mid-level jet and right entrance region of the 300mb jet. Both models continue to show, snow as the main precipitation type with the Canadian further north like the ECMWF but also allowing for more of a warm nose to work northward bringing a wintry mix in precipitation from snow, sleet, and possibly freezing rain.

Both 12z runs of the GFS/ECMWF ensembles seem to be closer than the deterministic runs with a swath of impactful snow across the area. The ECMWF Extreme Forecast Index draws a shift of tails contours of 1 across the southern half of KY with a contour of 2 across all of central TN into far south central KY. This makes sense give the current solution from the EURO.

At this time, like the idea we're seeing from both the ensembles, which is a nice blend of the two and seems to be more in the camp with the ECMWF. This shows impactful winter weather, mainly in the form of snow is expected over the weekend, mainly Saturday into Sunday. Keep in mind that any shifts north or south will cause significant changes to the forecast outputs over the next couple of days as we get closer to the event. We tend to see this, this far out as the models try to find a good solution. Finally, it is very likely there will be a sharp gradient in snowfall amounts as you go north from the main axis of heavy snow, which can also be a challenge once we start looking at snow amount's.

SUNDAY INTO MONDAY... Not to sleep on this as once this system moves off to the east, very cold arctic air will spill in and we could also see some very gusty winds. If we add snow on the ground then we have very cold temperatures with some potentially strong winds. Just felt this needed to be highlighted and not completely over shadowed by the main event over the weekend.

AVIATION /18Z TAFS THROUGH 00Z WEDNESDAY/

Issued at 1225 PM EST Mon Jan 19 2026

Sfc cold front continues to work eastward but the skies have cleared over the area. Other than so high clouds, it will remain VFR but we will have the gusty winds until about sunset then as large high pressure currently over the central US builds in over the Ohio and TN Valleys. Winds will become light and skies will remain clear and that will take us into the day tomorrow.

LMK WATCHES/WARNINGS/ADVISORIES

KY...Cold Weather Advisory from 10 PM this evening to 10 AM EST Tuesday for KYZ031>037-039>043-048-049. IN...Cold Weather Advisory from 10 PM this evening to 10 AM EST Tuesday for INZ079.