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KEY MESSAGES

* Quick-hitting system will bring a chance for winter weather and light snow accumulations on Friday, mainly across southeast IN and northeast KY. Additional chances for light snow are possible Friday night as lake-enhanced bands drop across the region.

* The weekend starts cold, but will trend milder into early next week with mostly dry conditions expected. The next chance for precipitation (rain) is expected by next Wednesday.

SHORT TERM /THROUGH FRIDAY NIGHT/

Issued at 325 AM EST Thu Feb 5 2026

This Morning through Tonight...

It is a cold morning across central KY and southern IN, though the magnitude of the cold temperatures varies between areas which continue to have stratus and areas which have cleared out. In areas where clouds persist, temperatures are generally in the low-to-mid 20s. In contrast, locations that have seen skies clear have fallen into the low teens and single digits, with a few locations even below zero as of 07Z. Through sunrise this morning, we'll be monitoring the potential for freezing fog to develop in areas where skies have cleared. So far this morning, any fog banks have largely been concentrated in low lying areas near bodies of water, so we've added patchy freezing fog mention in river valleys where skies have cleared. Stratus clouds should continue to sag to the south later this morning, likely leading to a quick drop in temperatures if skies clear before sunrise.

Today, an upper level speed max and vort lobe is expected to descend from the upper Midwest toward the Ohio Valley and decrease in strength, allowing a sfc front over Lake Superior to sag toward the lower Great Lakes. This disturbance will bring greater mid- and upper-level moisture into the area from the north, with areas that clear out this morning seeing clouds increase by midday and early afternoon. A few bands of light snow showers and flurries will try to move across Indiana later this afternoon and evening; however, dry air in the low levels should limit snow chances in our area. Temperatures will remain cold later today, with highs only expected to range from the mid-to-upper 20s along and north of I-64 to the low-to-mid 30s across southern KY. The sfc high pressure axis which is just north of the Ohio River this morning will sink across the area today, with light and variable winds becoming light out of the south by late this evening.

Tonight, a stronger upper-level disturbance will begin to drop from NW to SE across the Great Lakes and into the Midwest, with clouds increasing and moisture building down by early Friday morning. Temperatures should not be as cold tonight as this morning, with lows only falling into the 20s in many locations.

Friday and Friday Night...

By Friday morning, the influence of the aforementioned upper disturbance will cause a sfc cold front to drop toward the Ohio Valley from the northwest. As is typical for clipper systems, moisture will be limited; however, there should be sufficient combination of low-level and upper-level lift and moisture for an area of precipitation to develop just ahead of the cold front.

There are two sources of uncertainty with this system: first, how far southwest can it dig into the upper ridge and second, what precipitation types will be supported. On the first point, there is still some spread in the hi-res guidance, with the HRRR being farther to the NE while the NAM 3km and RRFS solutions dig more to the SW. In general, the chances for precipitation increase as you go northeast of a line from Madison, IN to Mount Vernon, KY. As far as precipitation types are concerned, most hi-res soundings show a bit of an above-freezing layer aloft on the SW edge of the precipitation area due to a lack of better saturation, with areas farther to the NE seeing the entire column fall below freezing once it saturates. As a result, would expect a narrow band of a mix of rain/freezing rain/sleet on the southwest edge of the precipitation, with snow more likely to the northeast. The main time window for this band of precipitation is expected between mid-morning Friday and mid- afternoon, with the sfc front clearing to the south by early evening.

Given the limited duration of this event and marginal thermal profiles, snowfall accumulations of over 1 inch are fairly unlikely at this time, though the greatest chances would be across our eastern and northern KY Bluegrass counties. Speaking of the marginal thermal profiles, areas across southern and western KY within the warm sector may approach 50 degrees on Friday before the cold front comes through, so there should be quite a variation in weather conditions across the area. Winds will also be breezy as the cold front passes, with wind gusts of 15 to 25 mph likely Friday afternoon.

Behind the front, strong cold advection will send temperatures tumbling Friday night, especially across northern KY and southern IN where temperatures may fall back into the teens. A secondary front combined with northerly low-level flow may bring another chance for some lake-enhanced snow as feeder bands drop south into the area Friday evening. Any accumulations with these bands shouldn't be too significant, as they should quickly pass to the south across the area; however, with crashing temperatures, even light snow accumulations could cause slick travel conditions Saturday morning.

LONG TERM /SATURDAY THROUGH WEDNESDAY/

Issued at 325 AM EST Thu Feb 5 2026

Over the weekend, there is fairly good agreement among the ensembles in the synoptic pattern, with NW flow in the mid- and upper- troposphere initially over the eastern one-third of the CONUS before gradually sliding out into the Atlantic by early next week. This pattern shift will be somewhat modified and slowed by a cutoff upper low which will drift across Baja California and northern Mexico over the weekend, and is currently expected to provide our next chance of precipitation around the Tuesday/Wednesday time period next week.

With the upper trough fully amplifying along the eastern seaboard during the day on Saturday, a favorable surface pattern for one more intrusion of cP air will set up as 1036 mb high pressure sinks into the Midwest. For most of the area, Saturday should bring mostly sunny skies, though this will be somewhat dependent on how persistent the streamer band of llvl moisture from Lake Michigan is, and where it ultimately sets up. Saturday night into Sunday morning, a mid-level vort lobe descending within the NW flow aloft is expected to drop from the Great Lakes toward the Appalachians. This will bring one more clipper system with light snow near the region, though the current ensemble consensus keeps precipitation just NE of the area. Something to watch for across the Bluegrass region if the guidance trends farther southwest. Sunday should begin the process of temperatures warming across the region; however, there is quite a spread in ensemble guidance with how quickly this occurs. In general, temperatures will be colder to the northeast on Sunday and warmer to the southwest, and there should be quite a strong temperature gradient across central KY and southern IN.

The warming trend is favored to continue into early next week, though just how warm temperatures climb could be modified depending on how long snow cover persists. Current NBM guidance is on the high side of most deterministic guidance, and this appears to be the correct thinking as snow depth appears to be too aggressive into early next week. As upper ridging moves over the region, sfc low pressure will begin to develop to the west and northwest of the Ohio Valley, allowing for more warm southerly return flow. While Monday and most of Tuesday are expected to remain dry at this time, by the latter half of Tuesday into Tuesday night, moisture return should be sufficient for precipitation to develop. ECMWF ensemble p-type guidance shows high confidence that the system during the middle of next week should bring rain, with temperatures expected to be above normal. This mid-week system should kick off a more active stretch of weather continuing into the end of next week and the following weekend. This is reflected in the CPC 8-14 day precipitation outlook, which shows a relative maxima in chances for above normal precipitation over the lower Ohio Valley.

AVIATION /06Z TAFS THROUGH 12Z FRIDAY/

Issued at 1235 AM EST Thu Feb 5 2026

Stratus cleared SDF earlier this evening and from satellite trends should clear LEX within the next hour. At BWG/HNB/RGA, MVFR stratus will take a few more hours to clear, and amendments may be needed later this morning depending on satellite trends. The main question mark over the next 6-8 hours is how much patchy fog develops as the stratus clears out. Have opted to keep fog largely out of the forecast for now, but we'll have to watch the 09-14Z time window for some VIS reductions. Otherwise, today, mostly VFR conditions are expected with light and variable winds. Toward the end of the current forecast period, winds should back to the south with mid- level clouds building down into Friday morning.

LMK WATCHES/WARNINGS/ADVISORIES

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