Friday Night: Mostly Clear, 39°F 

Saturday: Mostly Clear, 61°F 

Saturday Night: Clear, 42°F 

Sunday: Increasing Clouds, 75°F 

Sunday Night: Partly Cloudy, 56°F 

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General Discussion: 

Calm and cool conditions are expected to dominate the region throughout much of the forecast period, with temperatures around 10 degrees below the 30-year climatological average (71°F). A shift in the overall pattern will allow for seasonably average temperatures to return by Sunday, as temperatures are expected to rebound into the mid 70’s. Although timing and intensity are uncertain at this time, rain chances appear probable for the beginning of next week (40%). 

-Perrette 

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Forecaster: Perrette 

Date Issued: 05/01/2026 2200Z 

Technical Discussion: 

Key Messages: 

• Cool and calm conditions will remain dominant throughout the early part of the forecast period, as temperatures are forecasted to be 10-15°F below the 30-year climatological average (71°F) 

• A southwesterly wind shift will allow for seasonably average temperatures (71°F) to return throughout central Missouri. 

• Rain chances become increasingly likely for the beginning to middle part of next week, however much uncertainty remains regarding intensity, totals, and timing. 

As of Friday (21:00Z) central Missouri is experiencing elevated zonal flow (100-110kts) associated with a much larger trough, with said trough’s axis being oriented positively through the Upper Mississippi Valley through the Central Plains. At this same time frame, the associated low-pressure system is in the Upper Great Lakes region. This aforementioned low quickly begins to dissipate by Saturday (3:00Z) as it meanders northward out of the CONUS, and its associated trough also begins to weaken significantly. This is noteworthy because it will allow for the region to remain in a west-northwesterly flow regime aloft, allowing seasonably below average temperatures to continue throughout much of the region. This flow pattern will also dry out the column allowing for calm conditions to remain prominent throughout the region, and this is most noteworthy at the lower levels, where relative humidity values plummet to around 20-30% by Saturday (6:00Z). Our only chance for unsettled weather during this period would be seen in the form of upper-level cumulus development, as the general flow remains elevated and there are disturbances present at 500mb through the period of Friday 21:00-Saturday 6:00Z. This chance will only be present as cloud cover over the region because of the lack of major synoptic forcing, as well as the general lack of moisture throughout the column. 

On Saturday (9:00Z) the region enters much more of a meridional flow pattern, as the aforementioned trough begins to briskly skate through the Middle Mississippi Valley. By this time northwesterly flow becomes the dominate force driving the weather in central Missouri, once again doing a sufficient job at keeping our column cool and dry. There is another wave of mid-level disturbances present through Saturday (12:00Z-18:00Z), however, as mentioned before, due to insufficient moisture, no active weather is expected during this period. There is a chance for more elevated clouds, like Friday, assuming the mid-level disturbances can spark enough lift to generate cloud formation; however, at this time this appears unlikely (20%). 

By Sunday (15:00Z) the region enters more of a quazi zonal flow regime that takes on more of a westerly flow. This westerly flow becomes more southwesterly in the lower levels, with the LLJ strictly being out of the southwest by Sunday (18:00Z), flowing at 35-40kts. This change in the flow throughout the column will allow for moisture return to rebound throughout much of the Middle Mississippi Valley, bringing RH values into the range of 60-80 (Monday 6:00Z) percent in the mid-levels, and surface dewpoints into the mid 50’s. These factors will combine with a plethora of short waves throughout the column to create a moderate chance (70%) for cloud cover to begin developing by midday, where it will become much more consolidated by the overnight hours. The other effect that the region will experience due to this shift in the overall flow is a general warmup, as temperatures will climb back into the mid 70’s which is right around the 30-year climatological average of (71°F). 

Future forecasters should monitor future trends regarding intensity and timing of rain chances for the beginning of next week. 

-Perrette