textproduct: Louisville

KEY MESSAGES

* Cold Weather Advisory is in effect from 1 AM EST until 9 AM EST Sunday across the Bluegrass.

* A wintry mix of rain and snow is possible Tuesday into Wednesday.

UPDATE

Issued at 957 PM EST Sat Jan 31 2026

Over the past few hours, the coverage of light snow showers across central KY and southern IN has gradually subsided. Both the feeder band of moisture off of Lake Michigan and the broad llvl convergence have weakened as high pressure starts to nudge its way in from the west. With that being said, there are still a few bands of flurries and light snow at this time, with the most notable extending from near French Lick to west of Etown at this time. This band too should weaken as it gradually sags southward tonight.

On the nighttime microphysics satellite product, a clear gap in the low stratus can be seen across much of the state of Indiana as the boundary layer winds create a gap between the moisture-laden fetch off of Lake Michigan and Lake Erie. This clearing should move across portions of our CWA tonight, which will allow temperatures to drop as efficient radiative cooling takes place. There is some concern in the hi-res guidance (most notably, the HRRR) that elevated llvl moisture lingering over the area could cause freezing fog to develop as temperatures tank later tonight. While patchy freezing fog is certainly possible given the relatively high dewpoints, think it will be more limited in scope compared to the HRRR solution which is clearly too aggressive with radiational cooling (it drops Louisville to -13F!). For now, we'll monitor trends in obs across Indiana to see if increased fog messaging will be needed Sunday morning.

Otherwise, one more really cold night is in store across the area, with colder temperatures expected where clearing persists. Made some slight changes to overnight temperatures, particularly across southern IN, taking low temperatures to around or a few degrees below zero in many areas. Updated products will be sent shortly.

SHORT TERM /THROUGH MONDAY/

Issued at 434 PM EST Sat Jan 31 2026

A large upper trough covering the eastern three quarters of the CONUS is centered over Florida. This is pushing a closed low over northern Georgia away from the CWA and sliding the center of surface high pressure southeast from the Southern Plains towards the Ozarks. It's this high that is driving northerly winds and carrying moisture south from Lake Michigan, resulting in flurries over southern Indiana and central Kentucky.

Tonight, as the aforementioned upper low gets quickly carried off to the northeast, an area of upper riding rides the upper ridge southeast through the Midwest towards the Ohio Valley as winds ease with the nearing surface high. Some clearing is expected to begin with the best chances being over parts of southeastern Indiana and northern/north central Kentucky. Any clearing would help radiative cooling low temperatures. Low temperatures are expected to drop near 0 to 12 degrees. The Bowling Green area will likely be the warmer side of the CWA tonight as cloud cover lingers longer, holding in more heat. With up to 10 mph winds possible, wind chills could still reach to around -5 degrees east of Louisville into the Bluegrass. This is a more marginal case for a Cold Weather Advisory, but with it already in place with neighboring offices, we're keeping it. If we see more clearing, there is potential for temperatures to drop below the forecast.

Tomorrow, as the surface high begins to pass the CWA, winds begin to back towards the south as additional clearing continues. With cold air advection ending and some added sunshine, temperatures are expected to get a little warmer, making it into the low to mid 20s.

LONG TERM /MONDAY NIGHT THROUGH SATURDAY/

Issued at 434 PM EST Sat Jan 31 2026

Sunday night into Monday, northwest flow remains as a shortwave moves west to east over the area. This will bring at least cloud cover to the region, but light flurries will also be possible. This isn't expected to amount to anything as soundings show possible issues with the DGZ staying saturated and pockets of dry air below it.

Monday and Tuesday, surface high pressure remaining over the Southeast ahead of an approaching surface low will keep warm air advection in place. Temperatures warm above freezing with highs in the mid 30s to low 40s on Monday. On Tuesday, southern Kentucky could reach into the mid to even upper 40s, but this warm up doesn't come without consequences. As the surface low approaches the CWA, isentropic lift ahead of the system will cause precipitation chances to increase. Depending on the exact path the low takes will determine who gets rain and who gets snow. Model soundings show there isn't much of a warm nose. Temperatures are fairly uniform in the column, so sleet doesn't look very likely, just rain or snow. Current trends have the snow axis falling somewhere between north- central Kentucky and southern Indiana with rain to the south. It's also possible that snow on the northern side begins during the day along a more narrow strip before filling in later Tuesday night as the low nears. Snow totals could reach up to an inch or two. Behind the passing low, cold air advection returns. The northern half of the area currently looks to remain below freezing on Thursday.

At the end of the week, Friday of Friday night, a low pressure system moving through the Great Lakes could bring chances for additional precipitation as the system's cold front gets pulled through the area.

AVIATION /06Z TAFS THROUGH 12Z MONDAY/

Issued at 1247 AM EST Sun Feb 1 2026

IMPACTS: - Low Confidence in the development of patchy fog towards morning - Mainly VFR through the forecast period - Light snow continues from HNB to north of BWG.

Current nighttime microphysics satellite imagery is showing clearing skies around SDF and should start to see LEX scatter out and clear early on in the forecast period. Some model guidance has been suggesting that some patchy fog could develop with the clearing but looking up stream where skies have cleared over central/southern IN, we're not seeing this development. Decided to show some lower VIS to around MVFR for LEX/SDF towards morning with TEMPO group in case we see visibilities fall. Outside of that should have more clearing, winds out of the west around 5kts.

LMK WATCHES/WARNINGS/ADVISORIES

KY...Cold Weather Advisory until 9 AM EST this morning for KYZ031>037-039>043-047>049-056-057. IN...None.