Marine Weather and Tide Forecast for Columbia, MO

SHORT TERM
(Through Late Sunday Afternoon)
Issued at 224 AM CST Sat Dec 7 2024

Surface high pressure over the Deep South this morning will gradually move east today and Sunday. The southwest flow around this high will continue our warm up today, with temperatures warming another 10 to 15 degrees from yesterday. Most locations reach the 50s which is 5 to 10 degrees above normal for this time of year.
Dewpoints will also be increasing as well as modified Gulf of Mexico moisture gets pulled in around the departing high, so it won't be as dry as it was yesterday. Steady southwest winds and greater low level moisture will buoy overnight lows tonight, with the entire region remaining above freezing through the night.

Low pressure currently spinning over the Sonoran Desert will begin to drift east today and then open up into an open wave and track out into the Plains on Sunday. Ahead of this wave, low level flow turns more southerly and begins pulling even richer Gulf of Mexico moisture northward setting the stage for our next chance of rain.
There's pretty good agreement among the guidance that most of Sunday remains dry, but we do see increasing clouds through the day.
Temperatures remain warm, perhaps the warmest of the week. Southwest flow off the Ozarks aids in downslope warming likely resulting in the warmest temperatures in the St Louis metro, potentially in the low 60s. Cloud cover could stand to limit temperatures a bit, though, so if clouds arrive earlier then 60 may be harder to reach.

Kimble

LONG TERM
(Sunday Night through Friday)
Issued at 224 AM CST Sat Dec 7 2024

The richer surface moisture only makes it north to about Arkansas before the shortwave arrives, with showers and some thunderstorms developing in the warm/moist advection ahead of the trough Sunday night. Models continue to focus the axis of rain just to the southeast of our area, mainly over the Ohio Valley. However, there's still a strong consensus that at least our southeast forecast area gets some rain, although rain prospects decrease substantially to the northwest. The greatest uncertainty on the location of the rain is related to how far north the moisture gets before being lifted and transported northeast in the southwesterly mid level flow. Model solutions that move that moisture northward earlier produce more of a broad swath of showers across our area. Other solutions are a bit slower with that moisture transport, with convection initiating over Arkansas Sunday evening being the primary mechanism to move that moisture from the low levels to the mid levels, leading to a more focused axis of rain downstream over the Ohio Valley. With rich moisture available, heavy rainfall (in excess of 1 inch) is expected within the core of the rainfall axis, but confidence is high (>90%)
that this will remain southeast of our forecast area.

While Sunday's wave departs, we remain in the warm sector of the northern stream wave tracking through the Great Lakes on Monday. So we will see one more mild day on Monday before the cold front associated with that northern wave moves into our area. NBM interquartile range is actually smaller on Monday than on Sunday, lending even higher confidence in those mild temperatures in the 50s. Westerly surface winds won't have a downslope component and significant cloud cover is expected, so the higher end potential is lower on Monday than Sunday (lower chance of reaching 60).

The cold front moves through late Monday into Monday night, ushering in the latest Arctic air mass. Precipitation potential along this front has gone down in our area relative to prior forecasts. Most guidance sources don't produce precipitation until the front is well south of our forecast area Tuesday morning. As a result, NBM PoP has fallen largely below 15 percent. The main story will be the incoming cold air. Tuesday's highs will be 15 to 20 degrees colder than Monday with a stiff northwest wind giving the cold an extra bite.
Another surge of cold air Wednesday plunges temperatures even further, into the 20s and 30s for highs. Nighttime lows could potentially be in the teens or a bit colder if the right combination of calm conditions and clear skies lines up. Models diverge on how quickly to move the cold air out, so Thursday could be another cold day with highs around freezing or it could be the start of our next warm up. We will warm back up eventually, it's just how quickly that's uncertain.

Kimble

AVIATION
(For the 18z TAFs through 18z Sunday Afternoon)
Issued at 1146 AM CST Sat Dec 7 2024

Dry and VFR flight conditions are anticipated to persist through at least tonight with prevailing southwesterly winds, intermittently gusting to 18 to 22 kt. A 50-kt westerly low-level jet will develop this evening and persist overnight, resulting in marginal LLWS in the lowest 2000 ft AGL but a lack of directional wind shear and surface winds possibly taking much of the night to slacken should limit the overall impact. On Sunday, MVFR ceilings have the potential to develop across portions of the region during late morning into afternoon; however, it is uncertainty how quickly development will occur and how widespread they will be, warranting maintenance of VFR flight conditions in the current TAF package.

Pfahler

LSX WATCHES/WARNINGS/ADVISORIES
MO...None.
IL...None.