Friday Night: Chance of Fog. 66°F 

Saturday: Mostly Sunny. 88°F 

Saturday Night: Mostly Cloudy. 69°F

Sunday: Partly Cloudy. 87°F

Sunday Night: Chance (30%) of Rain. 64°F ============================================================================= 

General Discussion: 

Fog will be present for Friday night into Saturday Morning due to high moisture. Sky conditions will be mostly clear until late Saturday Night where moisture will promote a cloudier environment, temperatures in the upper 80s, and a chance (30%) for precipitation Sunday night (<0.02”). 

– Cooper

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Forecasters: Brickler, Cooper, Kotcher

Date Issued: 09/11/2026 5:00 PM CDT 

Technical Discussion:

Key Messages: 

• Weak winds and high surface moisture (>90%) will make fog likely Friday night into Saturday morning.
• A 30% chance of precipitation Sunday night could bring light showers in some areas.

Friday Night – Sunday:

Currently at the 250mb level, quasi-zonal flow persists throughout the majority of the forecast area. Near the MO/AR border, a prominent shortwave is present, creating areas of disturbance and increased vorticity values throughout the upper-levels. However, it is important to note that throughout all levels of the atmosphere, there is a noticeable dry slot in which no real effect coincides with those areas of higher vorticity and the shortwave. As the progression of the shortwave shifts further to the east, the heightened values of vorticity linger along with it creating a true zonal flow across much of the Midwest and Mississippi River Valley. Falling down to the lower levels of the atmosphere, moisture starts to build back up behind the aforementioned dry slot – primarily at the surface overnight. Because moisture and RH values are so high at the surface (>90%) as well as the near-calm conditions (<5 kts), fog is expected throughout the majority of mid-Missouri overnight into Saturday morning. Although, this burns off fairly quickly, leaving Saturday mostly sunny with temperatures in the upper 80s. 

A surface high-pressure system located at the AR/LA border generates a southerly flow throughout much of Saturday night into Sunday. This will cause temperatures to rise slightly compared to previous days, but should still be in the upper 80s. Along with the higher temperature values, moisture is brought back in from the south as well, creating ample cloud cover throughout Saturday night into Sunday.

Sunday Night:

In the upper-levels for Sunday night, weak but still noticeable forcing exists well throughout all layers of the atmosphere. Starting at 250mb, upper-level divergence is noticeable above mid-Missouri coupled with slightly increased vorticity values at 500mb as well. Continuing on down, 700mb show increased Omega values that coexist with ample amounts of moisture as well. 850mb is much of the same story – strong amounts of moisture as well as some weak interference with the LLJ create a forcing mechanism as well. Because of the aforementioned reasons there is a chance of precipitation for COMO, although due to the fact that all mechanisms or forcing are relatively weak, precipitation – if any – should remain in the trace values (<0.05”). Temperatures are also expected to drop into the low 60s due to this chance of precipitation.

– Brickler, Cooper, Kotcher