Monday, February 12, 2024 — Afternoon Forecast
Monday Night: Mostly Clear. Low: 28
Tuesday: Mostly Sunny. High: 54
Tuesday Night: Clear. Low: 34
Wednesday: Mostly Sunny. High: 61
Wednesday Night: Increasing Clouds. Low: 43
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Discussion:
Above average temperatures are expected to continue through the midweek, reaching the mid to high 50’s. Temperatures will start to taper off toward seasonal averages as a cold front comes through Wednesday night into Thursday morning. Precipitation is NOT expected with the passage of this front.
-Beam
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Forecasters: Beam, Jackson, Sallot
Date Issued: 02/12/2024 5:00PM CST
Technical Discussion:
A positively-tilted trough moved in from the four corners region of the Western U.S. and has migrated into the Central region. This trough has been shifting toward more of a neutral-tilt as it has propagated east toward Missouri. Cloud cover will remain limited Monday night and radiational cooling will set up, causing temperatures to dive into the upper 20’s-low 30’s across the area. A zonal flow regime will take place after this initial trough moves completely through the Central U.S. Multiple shortwaves take aim at Missouri throughout mid-week. The Polar Jet sweeps through the Iowa/Missouri border Tuesday evening but moisture will remain lacking across Missouri resulting in no impacts.
The NAM model will be relied on more heavily compared to the GFS as it handles the current setup more accurately. That being said, the NAM seems to have a moist bias compared to the GFS and has RH values exceeding 70% throughout much of the area Tuesday into Tuesday night. Precipitation is not expected however, even given sufficient lift, as low-level moisture is non-existent.
A secondary slightly positively-tilted trough will come through the Central U.S. early Thursday morning. This trough is interesting as models are in heavy disagreement with the amount of moisture in the mid-levels (GFS being more moist, NAM being more dry). I am leaning towards a more dry atmosphere (like the NAM shows) and RH values will remain higher to the north of Central Missouri, even given the decent amount of lift across the area. Despite limited vorticity advection across Central Missouri from the 06-12z Thursday timeframe, I don’t think it’s enough to aid in the formation of precipitation.
A surface low will ride across Southern Iowa within this trough with an attendant cold front that sweeps through Central Missouri between 09z-12z Thursday. With the moisture being confined to the north, precipitation is NOT expected for the area with the passage of this front. Future forecast shifts will need to monitor the cold air that comes in after the front as cold air advection looks to take hold of the area come Thursday morning (however, this looks to be stronger to the north). Winds will switch back to the northwest from the south with the passage of this front, helping to aid in a brief cool-down.
Temperatures will continue to remain above seasonal averages with this zonal flow taking over. Once the cold front comes through the area on Thursday morning, temperatures will start to dive back toward seasonal averages.
-Beam