Wednesday Night: Partly Cloudy. 48°F

Thursday: Overcast, Rain possible. 68°F

Thursday Night: Scattered Storms. 53°F

Friday: Scattered Thunderstorms. 76°F

Friday Night: Thunderstorms. 65°F

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General Discussion:

A sunshiny work week will end on a stormy note with clouds moving in starting Wednesday night. These clouds will continue building into overcast conditions on Thursday which will then further progress into scattered rain showers Thursday night. This will evolve into scattered thunderstorms on Friday and then isolated thunderstorms Friday night. Breakout your umbrella and raincoat for this one, as these storms have the potential to be severe.

-Cargill

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Forecasters: Cargill, Robinson

Date Issued: 04/24/2024 5:00 PM CDT

Technical Discussion:

Key Messages:

-Chances for precipitation will begin to increase Thursday night and continue to increase through Friday night.

-There is an increased chance for severe thunderstorms and heavy rainfall Friday and Friday night.

Both the NAM and GFS were used in the making of this forecast. This is because they both have similar predictions of the movement of an upper-level low-pressure system that will be causing much of the unsettled weather expected to occur.

The aforementioned low-pressure system will be pushing a significantly negatively-tilted trough into the CWA. In tandem with this event, a powerful shortwave will sprawl into mid-Missouri. With it comes significant upper-level divergence. At 500mb, strong vorticity and smoothed differential vorticity advection will be moving into the CWA as the axis of the trough moves further into Missouri. All of this provides ample upper-level setup and support for severe weather.

At the 700mb level, significant moisture is modeled to set in starting around mid-day Thursday. Additionally, significant omega values are modeled to move throughout the CWA. This occurs around the same time that the upper-level divergence at 250mb was modeled. So, there will be significant lift present for thunderstorm development going as far down as 700mb. Furthermore, at 800mb, there is also significant moisture that will not dry out until early Saturday, very similarly to 700mb. Additionally, there is a powerful low-level jet that will reach its peak intensity around 21z Friday. This will provide additional moisture to storm systems on top of the already exceptionally moist mid to low-levels.

At the surface, dew point temperatures greater than 60°F will set in starting mid-day Friday and will remain above that value through the rest of the forecast period. Additionally, a southerly wind shift will persist through the period. This will bring in warmer temperatures as the forecast period closes out.

Modeled soundings support the notion of severe weather moving into the CWA around late Friday into early Saturday morning. This is due to the soundings having large CAPE values, peaking at 1,041 J/kg on Saturday at 06z and strong speed and directional shear throughout the atmosphere. Additionally, CIN will get as low as -80 J/kg. This, coupled with other severe weather indice values conducive for strong storms, provide high confidence in the possibility of severe thunderstorms Friday into Friday night. Expect rainfall totals to reach at most a quarter of an inch Thursday night and at maximum a half inch on Friday to Friday night. Future forecasters should watch out for additional severe weather being forecasted for the late weekend.

-Cargill