textproduct: Louisville

KEY MESSAGES

* Light rain and mild temperatures this morning will give way to falling temperatures and a transition to isolated snow showers late afternoon through evening.

* Some light coatings of snow will be possible, mainly across SE Indiana into the Bluegrass region of central KY, and areas along and east of the I-75 corridor.

* Another system looks to move through on Friday and Saturday brining snow showers and snow squalls to the area along with cold temperatures. Some minor accumulations of snow will be possible. Very cold temperatures are expected late in the weekend and into early next week.

SHORT TERM /THROUGH TONIGHT/

Issued at 310 AM EST Wed Jan 14 2026

Current mid level water vapor imagery tells the tale as a deeper moisture plume is starting to overspread our region ahead of a sharpening shortwave trough axis. This feature will rotate in from the mid Mississippi River Valley later this morning. Ahead of this feature, slightly higher PWATs (.75" through the column) and some H7 frontogenesis will be enough to squeeze out some widespread light rain, especially Ohio River southward. Areas across southern IN will stay in the likely range with lesser amounts of a tenth of an inch or less. Areas along and south of the Ohio River will feature categorical pops, and should expect around .1" to .25" total through today.

At the surface, a cold front is poised to drop in from the NW later this morning through the afternoon, with temperatures likely dropping from that point forward. In other words, a non-diurnal temperature curve, and a likely unpleasant descent back into winter this afternoon. Will take a bit of time for the low level thermal profile to prep for a snow-supporting sounding, but with steepening low level lapse rates and surface temps quickly falling through the 30s we will see a transition in p-type. However, by this time the bulk of the deep moisture will be exiting, and we'll be left with more meager 1000-850 mb moisture. This should be enough to squeeze out some light to briefly moderate snow showers ahead of a secondary shortwave rotating in by late afternoon into this evening, and with saturation reaching into the bottom half of the DGZ we should see rates enough to reduce vis and perhaps put some streaky coatings on grassy or elevated surfaces through the evening, especially across SE Indiana and the Bluegrass region and down through the I-75 corridor where some upslope may enhance things a bit. Tough to tell for sure with temps rapidly falling, but do think roads will mostly be un-impacted given the warm antecedent conditions and some lag behind the falling air temp. Do have some minor concern about any wet-surface re-freezing as temps fall through the 20s later tonight. That being said, gusty winds usually take care of that pretty efficiently and will just monitor for now.

Once the surface cold front passes later today, look for gusty winds to persist through the remainder of the short term forecast. Peak gusts this afternoon will likely range in the 25 to 35 mph range once again. Thereafter, most gusts should range between 15 and 25 mph. As we move toward sunrise on Thursday morning, temperatures are expected to be in the upper teens and lower 20s. Given the winds, minimum wind chill values are expected to sneak into the upper single digits to low teens. Dress everyone warm for the Thursday morning commute! Could be a bit of a shock given the overall milder weather we've recently experienced.

LONG TERM /THURSDAY THROUGH TUESDAY/

Issued at 310 AM EST Wed Jan 14 2026

Thursday - Late Thursday Evening...

Brief period of dry weather expected during this window as shortwave ridging and surface high pressure traverse the area despite a broad eastern CONUS parent trough in place. Cold conditions will be in place with temps Thursday morning in the upper teens and lower 20s. The mercury doesn't climb a whole lot during the day given steady cold advection and the weak mid January sun angle. Most highs should stay confined to the upper 20s and low 30s, but at least there will be some sunshine.

Friday Morning - Saturday Night...

By Friday morning, focus shifts upstream to the next in a series of shortwave rotating through that aforementioned parent trough. A look at soundings/time heights for this system shows a notably moisture starved profile with the origin directly out of central Canada. Overall, the low level look to have a bit of trouble saturating, but do expect we'll see some light snow across the northern half or so of the CWA ahead of this next vort max. Main concern with this feature will be timing of light snow potentially impacting the Friday morning commute for areas along and north of the I-64 corridor where moisture is deepest. Given cold air in place ahead of this brief event, any light snow will accumulate. Not a lot of liquid equivalent with this system given the overall lack of moisture, however with a snow ratio around 15:1 we could get some light coatings for folks Friday AM. This one could be tough to message as amounts would not meet any 1" criteria, but impact could be enough to warrant some enhanced messaging. Something to keep in mind and discuss as we approach this event.

After any quick hitting snow on Friday morning, the rest of Friday (daytime) should be mostly dry in the subsident wake of the lead wave, and waiting on the arrival of the next and more potent shortwave. Temps should warm a above freezing during Friday PM thanks to some brief warm advection. NBM is going fairly aggressive with temps in the low and mid 40s for most, which will have to be done on a pretty pure warm advection component given fairly heavy expected sky cover. We'll see if temps may need to be a lowered a bit for this timeframe.

Models continue to agree on anomalously low H5 heights over our area heading into the weekend, and several vort lobes rotating through. The general idea is there for a snow showery, gusty, and cold stretch heading into the weekend. Overall, not a lot of snow expected from an amounts standpoint, however the Friday night into Saturday time frame appears to carry the most potential from an intensity standpoint as low level lapse rates steepen amid moisture reaching through the DGZ. Some low level instability combined with a favorable temp profile, and gusty winds through the mixed layer should result in brief moderate to heavy snow showers and even some pure squall potential with this setup. The cyclonically curved left exit region of an upper jet is favorable for snow squalls, and with supportive soundings, and the Snow Squall Parameter calling for values of 3-4+, it has my attention more than usual. Something we'll be keeping an eye on in the coming days, but at least we'll be into weekend traffic patterns instead of morning/evening commutes.

Sunday - Tuesday...

Broad troughing looks to remain in place over the eastern CONUS for the late weekend to early next week time frame. This will keep cold and occasionally gusty conditions in place, although it looks to be an overall drier stretch of weather with individual shortwave activity passing more to our north and east by this time. Overall lower confidence though given the complexity of the many shortwave interactions with the strength/placement of the parent trough. Temperatures will be cold with highs only in the 20s to low 30s each day. Lows will likely be in the teens each day, and perhaps some single digits in spots. Given winds staying up through much of the time, wind chills will also be a concern at times. Single digits are possible Sunday, Monday, and Tuesday mornings.

Extended Forecast Discussion...

Moving into the extended forecast period, the teleconnection pattern is expected to be in a -NAO/-AO/-EPO/Neutral PNA pattern. This supports the deep trough axis in the eastern CONUS with strong ridging across the western CONUS. The West Pacific Oscillation (WPO) is forecast to remain negative here as well. This would support a continued colder than normal pattern from the northern Plains east into the Great Lakes and into New England. The MJO has been hanging out in the null phase but is expected to pulse out into phase 6 near the beginning of the period. Typically phase 6 in January is mild, but here we will be in a rather cold period initially. However, the MJO spike into phase 6 may result in a short moderation of temperatures and the emergence of the SE ridge. While the dynamical models build this ridge, I'm not overly confident that it will grow all that much given the -WPO forecast by the models.

It does seem plausible that some retreat of the colder core of air will take place and locally we'll moderate our temps above freezing. It seems that we may see the development of a large baroclinic zone from the southern Plains into the Ohio Valley and into the Mid- Atlantic around 1/23-1/24. The dynamical models suggest this, but I expect to see rather poor run-to-run continuity here with how the models handle it. The baroclinic zone will lead us to higher than normal precipitation chances here. In theory, we should have a pretty decent cold dome in place which will probably be hard to scour out initially. However, any southern stream system that develops will have the potential to bring moisture and warmer air into the region. The net result here is that all threats could be on the table here (rain/wintry mess/snow). Signal analysis from early January has been pointing to a period of active weather in the 1/24-1/27 period.

While the MJO is forecast emerge in phase 6 at the beginning of the period, most model forecasts show a strong orbit into phase 7/8 by the end of January and into phase 1/2 by early February. This would be strongly suggestive another bout of cold weather for the eastern US to close out the month and into February.

AVIATION /06Z TAFS THROUGH 12Z THURSDAY/

Issued at 1247 AM EST Wed Jan 14 2026

Cloud ceilings will continue to lower early this morning with light rain commencing across the area. Initially, we'll stay VFR with little to no vis restriction, however eventually ceilings will settle into the MVFR range in the pre-dawn to around sunrise time range. In addition, vis restrictions in more steady rain will be possible around this time. A cold front approaches and passes late morning through the afternoon with SW and WSW winds veering to a NW component and gusting 20 to 25 mph. Could be a brief period of low MVFR or even IFR cigs at LEX before this frontal passage. Light rain becomes more isolated and spotty with frontal passage, and could see an end to precipitation with a few light snow showers later this evening. Won't advertise in the TAFs for now due to low coverage and confidence. Ceilings should begin to improve toward the end of this cycle.

LMK WATCHES/WARNINGS/ADVISORIES

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