Wednesday Night: Mostly Cloudy. 26°F
Thursday: Partly Cloudy. 45°F
Thursday Night: Decreasing Clouds. 29°F
Friday: Morning Fog; Mostly Sunny. 37°F
Friday Night: Mostly Cloudy. 21°F
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General Discussion:
As classes start to wrap up, expect cloudy conditions throughout Wednesday night through late Thursday night. An increase in surface moisture could lead to fog Friday morning throughout the mid-day hours. Also, over the next couple of days, temperatures will start at the average for this time of the year (mid-40s) and then begin to dip down below these amounts due to an arctic air mass tracking into the forecast for the weekend.
-Brickler =============================================================================
Forecasters: Brickler, Magnuson, Wernsman
Date Issued: 12/10/2025 23:00:00 UTC
Technical Discussion:
Key Messages:
- Cloudy conditions persist throughout the majority of the forecast period
- Temperatures will start to decline below average (mid-40s) starting on Friday
- Potential for fog Friday morning
Wednesday Night – Thursday
Current mid-Missouri conditions, including a quick dry slot late this afternoon, are due to the low-pressure system situated over the northeast continental United States. A cooldown has already started to progress due to the couple of cold fronts that passed through the area associated with this low-pressure system. The exact location of this low-pressure system has started to back its previous eastward progression and has created a longwave trough extending from the Great Lakes region into eastern Missouri/western Illinois. The 300mb jetstream follows this general longwave pattern and initially holds a northwest flow and then starts to level out to a zonal flow into the mid-day hours on Thursday. Because of this eventual change in flow, very little vorticity or lift is prevalent throughout the rest of the forecast period.
Cross-sectional and isentropic analysis reveals a dry air mass from the north ushered in by a strengthening low-pressure system originating over South Dakota early Thursday morning. This slot of dry air is mainly in the low- to mid-levels initially for this time. This will eventually get overtaken by a swath of moisture from the west-northwest analyzed from strong areas of isentropic upglide along this low-pressure’s warm front. This will in turn create a very moist atmosphere, creating clouds throughout all levels for the majority of Thursday. However, it should be noted that the warm front’s exact positioning could hinder the timing and movement of cloud cover. If that warm front is weaker and stalls (which is what some models suggest) then the line of cloud cover will generally be right over the forecast area. However, if the warm front moves through faster than expected and could cause warmer temperatures behind that warm front as well as less cloud coverage.
Thursday Night – Friday night
With the tracking of that low-pressure system, concurrent with the upper-level jetstream, it will move into the forecast area and continue east, bringing us an arctic air mass Thursday night into Friday morning giving us below average temperatures (mid-40s). This air mass will usher out any mid-level moisture throughout the night, but will leave enough surface moisture as well as a weak wind to bring a possibility for fog in low-laying areas Friday morning where winds remain below five knots. After the low-pressure system moves further into the east, high-level clouds are expected to linger and progress into a second band of moisture throughout all levels of the atmosphere into Friday night. Temperatures will persist to drop into the low-20s throughout Friday night as well.
Future forecasters should look for the lasting effects of the previously mentioned warm front as well as the potential for fog Friday morning.
-Brickler