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ACUS03 KWNS 280743

SWODY3

SPC AC 280742



Day 3 Convective Outlook  

NWS Storm Prediction Center Norman OK

0242 AM CDT Sun Apr 28 2024



Valid 301200Z - 011200Z



...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR EASTERN

NE...WESTERN IA...NORTHWEST MO...NORTHEAST KS...



...SUMMARY...

Severe thunderstorms will be possible on Tuesday from parts of the

mid/upper Mississippi Valley into the central/southern Plains.



...Synopsis...

An amplified mid/upper-level shortwave trough is forecast to move

eastward from the northern Rockies into parts of the

northern/central Plains on Tuesday, accompanied by a strong

mid/upper-level jet. A surface wave is forecast to move from the

central Plains toward the upper MS Valley, with a separate low

expected to largely remain in place across the southern High Plains.



...Upper MS Valley into the southern Plains...

Low-level moisture will stream northward through the day from the

southern Plains into the central Plains and upper MS Valley, in

response to the approaching shortwave trough. While the richest

moisture will likely remain displaced southward of the shortwave

track, 50s to near 60F dewpoints could spread as far north as

eastern NE/western IA and southern MN by Tuesday afternoon. This

moistening beneath relatively steep midlevel lapse rates will

support diurnal destabilization, with peak MLCAPE ranging from

around 500 J/kg across southern MN to greater than 1500 J/kg across

the southern Plains. 



Thunderstorm development is expected along a weak cold front Tuesday

afternoon, as diurnal heating weakens MLCINH. The greatest coverage

of storms and strongest deep-layer shear are expected from southern

MN into parts of eastern NE and western IA, in closer proximity to

stronger ascent attendant to the shortwave. A few stronger

cells/clusters will be possible, capable of producing large hail,

damaging winds, and possibly a tornado or two. Storm coverage and

deep-layer shear will likely decrease with southward extent, though

stronger instability into parts of KS/OK could support at least an

isolated severe thunderstorm threat during the afternoon and

evening. 



A Slight Risk has been added where confidence is greatest in overlap

of greater storm coverage and shear with more favorable instability.



..Dean.. 04/28/2024



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