####018004716####
ACUS02 KWNS 251732

SWODY2

SPC AC 251730



Day 2 Convective Outlook  

NWS Storm Prediction Center Norman OK

1230 PM CDT Thu Apr 25 2024



Valid 261200Z - 271200Z



...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF

EASTERN NEBRASKA/NORTHEAST KANSAS INTO NORTHWEST MISSOURI AND

WESTERN/CENTRAL IOWA...



...SUMMARY...

Severe thunderstorms appear likely on Friday from parts of eastern

Nebraska/northeast Kansas into northwest Missouri and Iowa, and

continuing southward into parts of the southern Plains and Ozarks.

Tornadoes (some strong), large to very large hail, and damaging

winds will all be possible.



...Synopsis...

A negatively tilted upper trough over the central Plains Friday

morning will continue to eject northeastward across the Upper

Midwest through the period. A 50-70 kt mid-level jet will accompany

this upper trough, and aid in strong deep-layer shear needed for

thunderstorm organization. A broad southerly low-level jet will be

in place from parts of the southern Plains/Ozarks northward to IA.

Low-level moisture will stream northward from the central Plains

into the parts of the Upper Midwest in response, ahead of a deep

surface low developing northeastward across NE/SD through Friday

evening.



...Eastern Nebraska/Northeast Kansas into Northwest Missouri and

Iowa...

Showers and thunderstorms will likely be ongoing at the start of the

period Friday morning across this region, associated with persistent

lift and the southerly low-level jet. Most of this activity should

tend to remain sub-severe, but isolated hail and gusty winds could

occur. In the wake of this morning convection, a narrow zone of

moderate instability will likely develop across parts of eastern

NE/KS ahead of a surface cold front/dryline. Better forcing

aloft/mid-level height falls associated with the upper trough should

remain on the northern extent of the low-level moisture return and

developing warm sector.



Still, most high-resolution guidance shows robust convective

development by mid Friday afternoon across the eastern NE/northeast

KS vicinity. Strong low-level and deep-layer shear will favor

supercells with attendant threat for tornadoes and very large hail

as these thunderstorms spread into northwest MO and western/central

IA through Friday evening. Given the degree of low-level shear

associated with the 45-55 kt southerly low-level jet, some of these

tornadoes could be strong. The surface warm front draped across

northern/central IA will serve as the northern limit for an

appreciable tornado threat, although some supercells could continue

to pose a threat for large hail even if they become slightly

elevated to the north of the warm front. Based on latest guidance

trends, the Enhanced Risk for tornadoes and large hail has been

adjusted a little northward across eastern NE into IA.



...Southern Plains into the Mid Mississippi Valley/Mid-South...

Initially strong to locally severe thunderstorm clusters are

expected to move across eastern OK/KS and potentially northeast TX

into AR and MO through Friday morning. This activity should pose at

least an isolated severe hail and damaging wind threat before it

eventually weakens. Some of this convection may persist or tend to

regenerate along the eastern periphery of the primary instability

axis, especially across parts of southern MO into AR. The eastern

extent of any severe threat remains uncertain, but favorable

low-level and deep-layer shear could support occasionally organized

convection into the mid MS Valley/Mid-South, with an isolated threat

for large hail, damaging winds, and perhaps a few tornadoes

persisting.



Farther west, moderate to strong instability and strong deep-layer

shear will support a conditionally favorable environment along the

dryline from eastern OK into northeast TX. In the wake of the

departing upper trough to the north, additional development along

the dryline across this region should remain very

isolated/conditional. Even so, any sustained cells would pose a

threat for very large hail and a tornado.



...Northwest Texas...

The dryline will retreat westward across parts of west/northwest TX

late Friday night. Isolated to scattered thunderstorms may form

prior to the end of the period into parts of northwest TX, in

advance of another approaching upper trough over the Southwest.

MUCAPE and deep-layer shear appear sufficient for organized

convection, and isolated large hail may occur with any elevated

thunderstorms that can develop early Saturday morning.



..Gleason.. 04/25/2024



$$