textproduct: Kansas City/Pleasant Hill

KEY MESSAGES

- Near Normal Temperatures This Afternoon

- Arctic Air Starts Moving in Late Thursday, Very Cold Weekend with Bitter Wind Chills

- Increasing Potential for Snow This Weekend, Timing of Higher Snowfall Rates Later Into Saturday Then Previously Advertised

DISCUSSION

Issued at 253 AM CST Wed Jan 21 2026

Modest H5 trough axis is currently oriented from eastern Nebraska into Central Kansas early this morning, with another weaker disturbance over southeast Colorado. Two areas of dCVA will result in two areas of lowering surface pressure through the day. The first low will continue to move into the TX/OK Panhandle Region, while other area of decreasing surface pressure moves into Iowa. A warm front currently sits just north of the IA-MO state line this morning, with cold front placed across northeastern Kansas. The northeastern surface low moving eastward eventually drags the cold front across the forecast area through the morning hours. We may see a few flurries in our northern zones as this passes through. Subtle H5 height rises primarily over the Sand Hills of Nebraska will strengthen a surface anticyclone across the Northern Plains into eastern Nebraska by late this morning and early afternoon, with surface pressure rises then extending into northwest Missouri. This should help to clear out the cloud cover this morning, and that trend can already be noted on GOES NT imagery. With clearing skies, daytime insolation will help temperatures climb back into the upper 30s and lower 40s across most of the area, with a decent amount of warming happening on the backside of the front. Therefore, the first boundary passage of the day will be a more notable moisture discontinuity than temperature. Secondly, there is still some warm air present between 925mb-850mb over the High Plains from adiabatic compressional warming off the Rockies. As the H5 jet streak drops south out of Canada, flow just about the boundary layer should provide another day of WAA, so when the skies clear up and provide modest mixing, should provide a boost to temperatures for the afternoon. Later into the evening, the closed H5 low that has been sitting over Central Canada sends another vort max toward the upper Midwest, and reinforces the height gradient needed to keep the H5 jet streak moving into the Central CONUS. This will also keep the surface anticyclone moving southeastward, likely centered over eastern Nebraska heading into the overnight hours and Thursday morning. This will be the start of Arctic Air moving in, but at some point the mid-level steering flow shifts northeastward and halts the movement of the cold airmass.

Heading into the afternoon on Thursday, a PV anomaly off the southwestern California coast promotes troughing over the southwestern CONUS that will start to send multiple rounds of short- waves into the southern Plains and the Gulf Coast. This will send weak dCVA that will attempt to lower surface pressure, but currently keeps bona-fide cyclogenesis closer to the Four Corners Region. But this may be enough of a disturbance to provide a few hours of low level southerly flow, coupled with clear skies from the approaching anticyclone over the eastern Plains resulting in temperatures reaching back into the upper 30s, perhaps lower 40s. Even with that Arctic Air sitting just a few hundred miles northward and active flow, inner-quartile spread is fairly narrow for Thursday High temperatures for lower 40s in much of the forecast area, with upper 30s for the northern zone. Thursday Night, a stronger surface anticyclone that has been developing on the anticyclonic side of the jet streak will quickly be forced southward into the northern and Central Plains, as the closed-low system sends another shot of vorticity across Central Canada into the Northern CONUS. This air pushes into the area, and will deliver a rapid decrease in temperatures, along with breezy northwesterly winds. This leads to a cold morning with bitter wind chills, especially along the IA-MO state line. Have issued an Extreme Cold Watch for few counties in our northeast zones with wind chills likely approaching the -25F threshold. For Friday afternoon, the troughing over the southwestern CONUS begins to influence the forcing that keeps dropping into the upper Midwest, and sends the surface anticyclone eastward, but the Arctic Airmass in place especially in northern Missouri. This now leads us into the snow forecast part of the discussion for the weekend.

Bottom line up front, northward shift in snowfall probabilities over the weekend. The better forcing is delayed, with greater snowfall rates more favored later into Saturday, with lingering activity into early Sunday. Late Friday could actually be completely dry here, with activity over the Central and Southern Plains, and perhaps western Ozarks. With the 00z cycle, the deterministic GFS and ECMWF are in slightly better agreement with respect to the 500mb pattern, specifically with taking the next strong shot of vorticity and mid- level heights falls from the Canadian system further into the Central CONUS, and this trough axis attempting to phase with the trough axis associated with the PV anomaly off the California Coast. Both have stronger dCVA that expands from the Four Corners Region into the southern Plains. Both of them keep this further west Friday afternoon than previous runs had, which is leading to the delay in forcing compared to previous forecasts. The differences, is that the GFS has the base of the southern trough axis much further into Mexico than the ECMWF. So during the day on Friday, low-level flow from the Gulf into the Mid Mississippi River Valley does turn southerly. The GFS takes longer transport better moisture, while the ECMWF after cyclogenesis is complete, keeps the center roughly on the Gulf coast from Texas into the Mississippi Delta, and therefore the ECMWF is quicker with moisture transport, and ultimately, forces moisture further northward. Both deterministic models have decreased the strength of the anticyclone across much of the Central and Northern Plains. The GFS actually has strong enough dCVA that it attempts to develop another cyclone that quickly ejects into the Upper Midwest. Not sure this is completely realistic though, especially with the presence of the southern trough axis. Regardless, this means that the GFS has better moisture transport later into Saturday and Sunday between 700mb-500mb then it had the past few days, but still has a very dry boundary layer. The ECMWF maintains more moisture throughout the entire column, and that is again due to the southern trough axis not digging as far south as the 00z GFS solution. All that to say, Friday, we may not actually see much in the way of precipitation for our area, as these two waves are looking more favorable to phase, but still may act separately in providing eventual mid-level support. Far southwest Missouri could see more activity. Saturday is where our forecast area will start to experience notable H5 height falls. ECMWF quickly depicts increasing Q-Vector convergence and moisture transport by Saturday afternoon, and a cold enough airmass in place, this would be a snow precipitation type. This same Q-vector convergence arrives with the GFS, but about 6 hours later than depicted in the ECMWF, and also delays the moisture transport. Therefore, timing of greatest snowfall rates is off between the two. ECMWF by the overnight hours eventually pushes the moisture across most of the area, while the GFS cuts it off early Sunday around Hwy. 36. Both models still show a sharp cut off on the northern edge of this snowfall axis, and makes sense with the dry air push that comes after the passage of the mid-level trough axis. When it comes to FGEN processes, stronger omega through the DGZ, lower static stability and negative EPV indicating CSI release, all this tracks south of the forecast area with current guidance, thus the heaviest snowfall axis is centered from eastern Oklahoma into the southern Ozarks and Tennessee River Valley. The lack of a notable baroclinic gradient across our area prevents your typical snow ratio enhancements from occurring in our area. But also results in the sharp cut off when dry air is not too far away.

For the actual forecast, the GEFS and other ensemble suites are painting a reasonable picture for potential snowfall outcomes, with probabilities of at least 1 inch of snowfall between 50-60 percent reaching nearly to Interstate 70, and 30-40 percent probabilities for at least 1 inch reaching to Hwy. 36. With a threshold of 2 inches, 40 percent probabilities have shifted northward nearly to Interstate 70. While some of the ensemble means now depict 2 to 3 inches of snowfall north of Interstate 70, this is being skewed by a few outliers that try to paint an absurd amounts snowfall based on a 10:1 ratio. And we did see the 00z deterministic ECMWF Kuchera snowfall map that has 7+ inches. Not willing to buy into that kind of solution with that dry air just a 100 miles away (at least not with this forecast issuance), along with our surface temperatures possibly being in the single digits. But that at least gives you an idea that the 10th-90th percentile spread is still quite wide, and would explain why the 2 and 3 inch probability of exceedance values are low, even though the mean output is here. Viewing plots of all members of various ensemble suites, it appears that some members are phasing the two 500mb trough axes, while others are going with a completely split flow regime that results in very different moisture transport. But the shift northward of 1 inch probabilities, along with the deterministic GFS finally shifting northward closer to the where the ensembles have been trending, is increasing confidence in areas along and south Interstate 70 seeing accumulating snow over the weekend. Due to the larger spread still present in these solutions, not ready to land on a specific snowfall range just yet. Amongst NBM members, the 25th-75th spread for most of eastern Kansas and Central Missouri is 0 to 3 inches. I think given the setup, doubtful areas along and south of Interstate 70 stay completely dry. But if the lack of boundary layer moisture that the deterministic GFS is realized, the mean snowfall output from ensemble guidance (2 to 3 inches) will be very difficult to realize. Over the next couple of model cycles, the trends to watch will be 1.) How the southern tough axis digs and phases and 2.) In what direction do the preceding surface anticyclones from Wednesday and Thursday exit the area (this has implications for moisture return).

AVIATION /12Z TAFS THROUGH 12Z THURSDAY/

Issued at 519 AM CST Wed Jan 21 2026

High pressure moving will clear skies out today. Winds expected to pick up and shift as a front moves through the area. A few passing high-level clouds possible later in the day. Winds expected to diminish late in the evening.

EAX WATCHES/WARNINGS/ADVISORIES

MO...Extreme Cold Watch from late Thursday night through Saturday morning for MOZ005>008-015>017. KS...None.