Monday, April 1st – Afternoon Forecast

Monday Night: Severe Thunderstorms Likely: All severe hazards, including large hail and damaging winds and tornadoes (some strong) are possible. Low: 56°F

Tuesday: Light Rain Early, Staying Cloudy. High: 56°F

Tuesday Night: Decreasing Clouds. Low: 37°F

Wednesday: Partly Cloudy. High: 49°F

Wednesday Night: Decreasing Clouds. Low: 33°F

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General Discussion:

Severe Thunderstorms are likely this evening, becoming more widespread overnight. All severe hazards including the risk for large hail (some 2+ inches), damaging wind gusts (some in excess of 80mph) and tornadoes (some strong) are all possible. Stay weather informed after the sun goes down as the threat only ramps up! Temperatures will continue to drop through the day Tuesday.

Beam

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Forecasters: Beam, Jackson, Sallot

Date Issued: 04/01/2024 4:00PM CDT

Technical Discussion:

Key Messages:

1. Severe weather outbreak expected – all hazards possible including damaging winds, large hail, and tornadoes.
2. Warmer temperatures will be felt after these cold front’s effects.

Overall Synopsis

A large upper-level trough will move through Missouri through Wednesday and a ridge will build in behind it on Thursday. This very deep trough will lead to a potential multi-faceted severe weather outbreak across the central plains into the midwest. After the cold front comes through, temperatures will continue to drop through the day Tuesday. The morning hours will be the warmest part of Tuesday. The ridge following in the footsteps of the trough will lead to a warm up late week. Another low pressure is visible following the ridge, so future forecasts need to watch the development of an omega block. Moisture in the mid and low levels look to stick around through Tuesday night, where we might start to get some sun peaks on Wednesday.

Severe Weather Potential

As the jet streak rounds the base of the trough going into this afternoon, convergence at the surface will become widespread across the central plains and midwest as the exit region of the upper-level jet becomes prominent. A mid-level shortwave will ripple its way into Missouri late this afternoon into evening. This shortwave will seem to be the initiating mechanism for severe weather across Kansas and Missouri. There is ample lift at the mid-levels as well as moisture to support precipitation from the afternoon into the overnight hours. It has been very cloudy all day today in central Missouri, which is keeping temperatures on the lower end. The tornado threat is going to be very dependent on if the capping inversion present in the 18z KCOU sounding gets eroded enough due to daytime heating AND how the low-level jet evolves throughout the afternoon. Looking into specific severe weather parameters, mixed layer cape is forecast to be ~1500 J/kg. This will be higher if the sun can peak out in central Missouri by the time storms initiate. Per model guidance, the low-level jet will increase in strength and coverage from the evening into the overnight time frame. A lesser tornado threat exists during the afternoon as most storms will be rooted above a pretty stout inversion, but the tornado threat will start to increase into the late evening/overnight hours as the low-level jet kicks in. Forecast soundings from the HRRR show low level wind shear increasing into the overnight hours. The highest tornado threat exists for parts of eastern and southern Missouri, where clearing is starting to occur and the low-level jet is strongest overnight. Initial supercells could form along a warm front that is draped across Northern Missouri and along a dryline located through the southern plains around 21-22z. These supercells will eventually form into a QLCS around 00z with 0-3km bulk shear vectors being somewhat perpendicular and greater than 30 knots into the evening/overnight hours; this QLCS should have an embedded tornado threat across southern Missouri. These tornadoes could be potentially strong (EF2+) into the night as effects from the LLJ are felt.

-Beam