Marine Weather and Tide Forecast for Columbia, MO

SHORT TERM
(Through Late Tuesday Afternoon)
Issued at 237 AM CDT Mon May 25 2026

Surface ridging extends from the Great Lakes Region into the mid- Mississippi Valley this morning with mainly clear skies overhead.
Surface observations show winds have settled or lightened to calm/variable. The light surface flow and narrow dewpoint depressions could support patchy, mainly light fog again this morning. Fog potential will be best adjacent to river valleys and low-lying areas with higher soil moisture content from recent rainfall.

Memorial Day closes out the holiday weekend with near normal temperatures and dry conditions. Light, easterly surface flow will keep moisture at comfortable levels with some scattered afternoon clouds primarily south of I-70. HRRR/RAP are rather bullish with afternoon mixing, allowing dewpoints to drop into the 40s. This signal isn't as strong in medium/long range guidance, but even then low to mid-50s is comfortable with highs near 80 degrees. Scattered afternoon clouds develop primarily along and south of I-70 and that may be the extent of impact on sensible elements with trends migrating precipitation chances to the south of the CWA

Between tonight and Tuesday, a stagnated upper level low over eastern Texas begins to lift to the northeast as mid-level height rises subtly build northwestward. The weak front that just slipped to our south will lift back to the north Tuesday advecting moisture back into the region. Diurnal-driven showers and a few thunderstorms are possible, but will largely be limited to areas of southeast Missouri and southwest Illinois. A narrow ribbon of MUCAPE reaches between 2000-25000 J/kg along the advancing boundary, coinciding with higher HRRR probabilities (40-70%) for measurable rainfall.
However, even these probabilities are highly variable between locations within the broader spread of precipitation chances. This is typical of convective potential with highly variable rainfall in short distances. Fortunately, with shear below 20 knots, what forms is not likely become well-organized, but will have the potential to provide a brief period of heavy rain at effected locations. Most activity dissipates after sunset as diurnal support is lost.

After Tuesday morning lows in the mid-50s to low-60s, high temperatures return to nearly identical levels as today with highs in the upper 70s to low-80s.

Maples

LONG TERM
(Tuesday Night through Sunday)
Issued at 237 AM CDT Mon May 25 2026

The upper low that originates from eastern Texas progressively opens and becomes indiscernible Tuesday into Thursday. The northward progress of the weak front slows and eventually stalls as fragments of vorticity linger overhead. This draws a pool of higher theta-e northward with higher precipitation chances following diurnal trends. Disperse QPF plumes do little more than provide confidence that rain will become more likely from Tuesday onward. 24-hour run- to-run trends in the ECMWF and GFS ensemble show a delaying trend at the front end of the potential Tuesday afternoon/evening, maintaining a mostly dry forecast outside of southeast Missouri and southwest Illinois.

By Wednesday, the weak lifts to its destination, lining up somewhere along the I-70 corridor. PoPs become less confined and cover the CWA through the day Wednesday with isolated to scattered showers becoming relatively more broadly represented through the afternoon period as instability builds. Despite surface instability peaking between 2500-2700 J/kg, weak flow persists with shear values at 20- 25 knots or less. Given the weak flow, thunderstorms will become more vertically structured, leaving little room for well-organized convection. The greatest impact from this activity will be lightning potential and pockets of locally heavy rainfall as PWATs climb to 1.5-1.7 Wednesday afternoon.

Diurnal thunderstorm potential will be the theme through the end of the work week. Ensemble IQRs show a subtle increase in spread heading into next weekend, though the characteristic to temperature behavior is persistent and nearly flat several days out. This provide confidence that air will remain mild with variability driven by the extent of cloud cover and cooling caused by afternoon thunderstorms. One of the main drivers of the spread is likely to be a surface high that builds southeast from Canada into the Great Lakes Thursday into Friday. This shifts the weak boundary back toward the south/southwest as a backdoor cold front stalls in the Midwest. The southwest extent of the ridge orients the boundary along the Mississippi River, serving as the dividing line between dry conditions to the east and precipitation chances to the west.
Its along this divide where precipitation data spread is highest due to placement differences between solutions.

The divergence between ensemble guidance keeps at least low chances going into next weekend, though there's a downward trend in the potential. If deterministic guidance comes to fruition, especially the ECMWF, the forecast would lead drier in time with another backdoor cold front dropping north to south and shunting precipitation southward along with it.

Temperatures range from near to slightly above normal with highs in the upper 70s to mid-80s and lows in the 60s.

Maples

AVIATION
(For the 12z TAFs through 12z Tuesday Morning)
Issued at 426 AM CDT Mon May 25 2026

Patchy river and valley fog is leading to MVFR visibilities around KSUS this morning and likely at KJEF, as well. Fog quickly erodes this morning after sunrise. East and southeasterly flow increases by late morning, but high pressure remains in control with sustained winds peaking at 5-10 knots through this afternoon.

VFR conditions are expected outside this morning's patchy fog.

Maples

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