Monday, February 19 – Afternoon Forecast
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Monday Night: Mostly Clear. Low: 32°F
Tuesday: Sunny. High: 61°F
Tuesday Night: Partly Cloudy. Low: 42°F
Wednesday: Partly Cloudy. High: 69°F
Wednesday Night: Light Rain. 50°F
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General Discussion:
After cloud cover moves out of Missouri tonight, another warmer than average day is expected tomorrow. By Wednesday we’ll warm up into the mid to upper 60s before cloud cover becomes widespread Wednesday night. Along with this cloud cover there will be a chance for light rain.
-Jackson
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Forecasters: Jackson, Beam, Sallot
Date Issued: 2/19/2024 5:00 PM CST
Technical Discussion:
Key messages:
- Cloud cover will dissipate throughout the overnight hours after a trough/low-pressure system exits Missouri.
- Above average temperatures continue throughout the forecast period with help from southerly winds and sunshine.
- Another trough/low pressure system is expected to move through Wednesday night into Thursday, bringing chances for light rain and possibly thunderstorms.
A weak trough/low pressure system is traversing over Missouri this afternoon and evening which is bringing mid to upper-level cloud cover along with it. This is a weak system because there is limited moisture throughout all levels of the atmosphere, there is little to no omega and vorticity in our forecasted area. Therefore, no rain is expected throughout the passing of this system.
Moisture is hard to come by behind this trough which is why sky conditions will quickly clear up through the overnight hours. This will warrant radiational cooling to take place tonight and will result in temperatures falling into the low 30s by sunrise tomorrow. The trough/low pressure system will exit tomorrow morning and a ridge takes over as the dominant flow. Winds shift back to the south on Tuesday which will be coupled with ample sunshine. This will lead to temperatures breaking the 60-degree mark by the afternoon hours.
By Wednesday, our attention turns to a trough/low pressure system that will be passing over Nebraska and Kansas. This will first assist in the warmup process as it brings southwesterly flow into Missouri. This southwesterly flow will also assist in advecting more moisture overhead, leading to increasing cloud cover throughout the day. Model 1000-500 mb thickness output hints that Missouri will have organized solenoids across the area throughout all of Wednesday into Thursday morning. This is a setup for warm air advection since these solenoids have a southwest to northeast track. So, even with increasing cloud cover, temperatures are expected to climb into the upper 60s through the afternoon.
As this trough/low pressure approaches Missouri Wednesday night, uncertainty arises as models (GFS and NAM) are in heavy disagreement about the aspects of this system. Confidence is high that a cold front will be the culprit for light rain and thunderstorm chances through this time period. Both models also show that there will be better omega and vorticity associated with the trough/low-pressure system compared to the one passing today. This would mean a better environment for rainfall and thunderstorms, but the GFS has lackluster moisture while the NAM is much more aggressive with this component. Right now, light rain can be expected Wednesday night into Thursday with the possibility to hear rumbles of thunder.
Future forecasting shifts should continue to monitor the situation Wednesday night into Thursday and look for better agreement among models. Also, monitor the components of this system as there are hints of strong to severe thunderstorms in central Missouri from some model outputs.
-Jackson