Marine Weather and Tide Forecast for Lansing, KS

DISCUSSION
Issued at 241 PM CST Fri Dec 12 2025

Amplified H5 ridge axis currently sits over the Pacific just off the west coast of the CONUS, with strong northwesterly flow oriented from British Columbia into the western Ohio River Valley. Objective analysis as of 20z is showing a strong 120+ KT jet streak at 300mb pushing across Iowa into Western Illinois, with 100 kts hitting our northeast counties from Kirksville and northward. This is steering a strong surface anticyclone out of Canada, and 20z objective analysis indicates this feature is centered over the northern High Plains, but surface pressure rises extend into the eastern Plains. A strong Arctic Airmass is associated with this strong anticyclone, and there a few notable thermal boundaries associated with this. The first one is a notable temperature and wind shift, that is currently moving through eastern Iowa, and its trailing edge may get northern Missouri resulting in some scattered flurry activity as the evening progresses. But overall, this first boundary will be fairly uneventful for our forecast area. Surface anticyclone pushes into the North-Central Plains of the Dakotas during the overnight hours.

Saturday, another cold front gets pushed ahead of the surface anticyclone. A lobe of vorticity swings around the backside of an H5 closed-low system over the Northern Great Lakes Region, that will provide mid-level lift above low-level convergence with the next thermal boundary. Another temperature drop of 10-15F is associated with this boundary, with reinforced northwesterly winds. This boundary though will also have a notable moisture discontinuity, with most of the dry air located behind the front, as well as behind the lift supported by the strong CVA into eastern IA, western IL, and far northeast MO. Along with this convergence, deterministic model guidance continues to depict a stronger FGEN band developing a maximum between 1000mb-850mb, and another maximum between 700mb- 500mb. With the cold air settling in that will help to promote growth of bigger dendrites from north-central Missouri into Central Illinois. Model soundings are a bit messy thermodynamically, indicating two productive DGZ layers, one close to the surface and another further up. The upper DGZ layer may be able to play a seeder- feeder role, allowing dendrites to fall through a decent layer of supercooled droplets. As a result, snowfall ratios at 15:1, perhaps higher, will be possible for a few hours, primarily northeast of a line from Kirksville MO to Princeton MO. For our far northeast counties, this could favor 1 to 2 inches, with perhaps 2 to 4 inches in Schuyler County and areas northeastward. 12z HRRR probability matched mean values are not much greater than the HRRR mean 24 hour snowfall values, but both fields depict the area of favorable heavier bands. In collaboration with surrounding offices, have included Schuyler County MO in a Winter Weather Advisory on Saturday, as this is the location where great snowfall accumulations in our forecast area are likely to occur. Ensemble probabilities hold a 40-50 percent chance for at least 1 inch of snowfall in our northeast. The NBM probabilities were a bit lower, but not sure the drastic northeast shift will be fully realized that resulted in lower probabilities for the NBM. Most guidance is showing a fairly sharp gradient on the southwest edge of this snowfall axis. Some areas may see just above 1 inch of snowfall, and just flurries 15 miles southwest of it. Surface boundary pushes through most of Missouri between 00-01z tomorrow night, with a 700mb boundary perhaps still present over the Northeast Missouri, but most of the upper-level support for lift will move into Central IL, ending most of the accumulating snowfall for our northeastern counties. A quick note about freezing drizzle potential late Saturday afternoon into early evening, from central MO to western MO/ eastern KS. The NAM this morning came in with slightly better moisture in the lower levels with no ice introduction, which would suggest potential for patchy freezing drizzle. The RAP this afternoon has changed its tune every hour. The GFS is very dry in the boundary layer for the southwestern third of the forecast area. Ensemble probabilities are all less than 5 percent for freezing drizzle potential. Therefore, freezing drizzle is being left out the official forecast for now, but moisture trends within the boundary layer will need to be monitored closely.

After Saturday, the surface anticyclone keeps pushing the Arctic Airmass through, bringing some of the coldest temperatures that most locations have seen this Winter season. Sunday morning lows will be in the single digits across nearly the entire forecast area, and perhaps a tad below zero in our northeast, especially if there is a fresh snowpack on the ground. By Sunday morning, this is expected to yield Wind Chill Values below zero, with values between 12 to 19 below zero in our far northeast. This has prompted the issuance of a Cold Weather Advisory for our northeastern counties through late Sunday morning. Highs on Sunday will remain in the 20s for our southwestern CWA, will the northeast will struggle to reach the teens.

For the start of of next week, the strong surface anticyclone moves into the Gulf Region, and a short-wave trough moves out of the southwestern CONUS and will provide stronger south-southwesterly flow into the lower Missouri River Valley, which will push our temperatures back into the 40s, and perhaps even into the 50s by the the middle of next week. Inner-quratile spread is fairly large for temperatures, this may depend on how fast/slow the anticyclone moves into the Gulf Region and allows the WAA to take place. Ensembles are showing low end probabilities for some precipitation Thursday, but a lot of those are concentrated east of Hwy. 63 outside of the forecast area. Moisture return for Central MO to eastern KS may be very questionable for precipitation chances through the middle to end of next week.

AVIATION /06Z TAFS THROUGH 06Z SUNDAY/
Issued at 1119 PM CST Fri Dec 12 2025

Ceilings continue to be a challenge over eastern KS and western MO, with the area seeing a mix of VFR to low MVFR ceilings, obscured by higher-level clouds, making tracking/timing them into any point a challenge. Model guidance is also handling the lower moisture poorly. Overall, for the first 6-12 hours of the forecast, a mix of VFR to MVFR ceilings are forecast with the trend to all MVFR as Clipper system moves across the middle of the country brining light snow to northern MO and IA. Winds will remain northerly through the forecast but should increase this afternoon behind a strong cold front.

EAX WATCHES/WARNINGS/ADVISORIES
MO...Cold Weather Advisory from 9 PM Saturday to noon CST Sunday for MOZ006>008-016-017-025.
Winter Weather Advisory from 6 AM to 4 PM CST Saturday for MOZ008.
KS...None.