textproduct: Louisville

KEY MESSAGES

* Patchy fog is possible tonight, with isolated slick spots possible Friday morning where temperatures fall below freezing and dense fog occurs.

* Chances for light rain return across southern KY late Friday into Saturday morning.

* Dry weather and seasonable temperatures are expected for most of the weekend, with warming temperatures expected early next week.

SHORT TERM /THROUGH FRIDAY NIGHT/

Issued at 321 PM EST Thu Jan 1 2026

This afternoon, mostly sunny skies are present over the southern two- thirds of the forecast area, with temperatures surging into the upper 40s and low 50s. Mainly along and north of I-64, stubborn low clouds have persisted through much of the day, with temperatures stuck in the low-to-mid 30s. The dividing line between these two areas is a now washed out cold front which is expected to retreat slightly to the north through the afternoon and evening hours. Clouds should begin to scatter out on the southern fringe of the cold air mass, though portions of the northern KY Bluegrass and southern IN are likely to remain cooler and have more clouds through sunset.

This evening into the early overnight, aside from increasing high clouds, most of the area should see clear skies, allowing temperatures to cool quickly after sunset. Current dewpoint/crossover temperatures are in the mid 30s across central and southern KY, so with forecast lows in the upper 20s and low-to- mid 30s, think at least patchy fog will be possible tonight. If the fog is particularly dense, like in sheltered valleys and near bodies of water, there could be a few slick spots Friday morning given temperatures near or below freezing. At the same time, the low clouds may try to make a return late tonight as the sfc front gets another southward push. Wherever low clouds fill in, temperatures will be milder (likely low-to-mid 30s) and any fog should dissipate.

Any lingering low clouds should dissipate during the late morning hours on Friday, though mid- and high-level clouds will continue to increase from the west ahead of the next system. Temperatures should again vary from north to south, with highs Friday afternoon expected to range from the upper 30s and low 40s across the northern CWA to the upper 40s and low 50s across the southern CWA.

The system referenced above is expected to develop near the TX/OK border Friday morning as upper-level shortwave energy ejects across the central Rockies. A fairly zonal upper-level steering pattern should cause sfc low pressure to track eastward into the TN valley Friday night into Saturday morning. How far north the richest moisture makes it with this system is uncertain, with the ECMWF and most of the 12Z hi-res guidance farther south, while the GFS is farther north. There is still a significant possibility that the entire area remains dry with this system, resulting in little more than increased cloud cover. Regardless, the best chances for precipitation Friday afternoon into Friday night should be along and south of the Cumberland Parkway. At this time, the most likely QPF amounts are less than 0.25", with the probability of exceeding 0.25" maxing out at around 40% along the TN border. Soundings suggest that precipitation should fall as rain, as near sfc temperatures should be in the upper 30s and low 40s in areas where precipitation is expected. Farther north, where it should be dry, low temperatures Saturday morning should be in the upper 20s and low-to-mid 30s.

LONG TERM /SATURDAY THROUGH THURSDAY/

Issued at 321 PM EST Thu Jan 1 2026

By Saturday morning, our area should be on the back side of a system moving from the TN Valley into the Carolinas, with clearing from NW to SE expected during the day on Saturday. For much of the remainder of the weekend, the entire region should be within a fairly quiet weather pattern with NW flow in the mid-to-upper levels and sfc high pressure settling into the area. From Saturday afternoon through midday Sunday, light northerly flow will provide weak cold advection, which should be counteracted by sunshine Saturday afternoon and most of the day on Sunday. Temperatures should be fairly seasonable over the weekend, with highs generally in the 40s and lows in the 20s Sunday morning.

Sunday night into early next week, warming temperatures are expected as the synoptic pattern shifts to the east, causing flat upper ridging to spread east of the Mississippi valley and placing our region on the back side of sfc high pressure. This should allow warm return flow to begin Sunday night, though dry weather should continue as the nearest sfc low passes over the upper Great Lakes. Mild and dry weather is expected Monday and Tuesday as persistent S/SW low-level flow continues warm advection into the region. At this time, Tuesday appears to be the warmest day in the current extended period, with many locations favored to reach at least the upper 50s, if not the low-to-mid 60s.

By the middle of next week, gradual erosion of the upper ridge over the south central and southeast US should allow for precipitation chances to return. Tuesday night into Wednesday, a shortwave crossing the lower Great Lakes will bring a chance for light rain, though moisture with this system is largely unimpressive. A more significant system is showing up in extended-range model guidance for the end of next week, though guidance still displays a healthy spread in the track and impacts. Overall, mild weather should continue through the end of next week, with the pattern trending more unsettled by the 01/08-09 time period.

AVIATION /00Z TAFS THROUGH 06Z SATURDAY/

Issued at 604 PM EST Thu Jan 1 2026

Surface frontal boundary stalled out across northern KY this afternoon has retreated northward back into Indiana this evening. Cigs across the region look to steadily improve this evening with VFR conditions expected after 02/01Z. The VFR conditions will likely not hold as another slug of moisture drops down into the region from the northwest late tonight. This should bring cigs back down into the MVFR range. Winds will remain light overnight at all the terminals, and should continue to be light on Friday. MVFR cigs will likely found in the morning, but should increase back to VFR by late Friday afternoon.

LMK WATCHES/WARNINGS/ADVISORIES

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