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ACUS01 KWNS 030557

SWODY1

SPC AC 030555



Day 1 Convective Outlook  

NWS Storm Prediction Center Norman OK

1255 AM CDT Fri May 03 2024



Valid 031200Z - 041200Z



...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF

WESTERN AND CENTRAL TEXAS...AND THE SOUTHERN NEBRASKA/KANSAS

VICINITY...



...SUMMARY...

Scattered strong to severe storms will be possible Friday afternoon

into early Saturday morning over parts of the central/southern Great

Plains, and over the central Plains, beginning late afternoon/early

evening.



...Synopsis...

An upper low initially over the northern Plains/southern portions of

the Canadian Prairie Provinces is forecast northeastward into/across

western Ontario with time.  As this occurs, a short-wave trough will

advance eastward across the northern Intermountain region through

the day, and emerge into the northern and central Plains through the

second half of the period.  Meanwhile, a much weaker disturbance is

forecast to move eastward along the southwestern U.S./Mexico border

and begin affecting the southern High Plains area by late afternoon

before moving across the southern Plains overnight.



At the surface, a developing cold front is forecast to shift

southeastward into the central Plains through late afternoon, and

then continue eastward/southeastward overnight.  Meanwhile, a

dryline will mix gradually eastward across the southern High Plains

through the afternoon.



...Portions of western Texas including the South Plains/Big

Country/Concho Valley...

As a very moist low-level airmass across western and central Texas

warms through the day, substantial destabilization will occur. 

Mixed-layer CAPE values will likely reach 3000 to 4000 J/kg east the

dryline, which is expected to be mixing slowly eastward across the

South Plains and eastern portions of the Permian Basin near peak

heating.  By late afternoon, storm development is expected from the

Panhandle south to/across the Rio Grande, with the most numerous

storms expected within a zone extending from the South Plains to the

Big Country, and south across the Concho Valley.



While flow through the lower and middle troposphere will not be

particularly strong, veering winds with height, and ample high-level

flow, will support organized/rotating storms -- particularly given

the very favorable thermodynamic environment.  Very large hail will

likely occur with the strongest storms, along with locally damaging

gusts.  A tornado or two may also occur, though overall risk should

remain a bit tempered by somewhat modest low-level flow/shear.



Into the evening hours, some congealing/upscale growth of convection

is anticipated, which should gradually spread

eastward/east-southeastward toward/into central Texas -- accompanied

by risk for damaging winds and hail.



...Southern Nebraska southwestward across the western half of

Kansas...

Modest northward return of low-level moisture across Kansas is

expected to commence ahead of the developing cold front through the

afternoon.  Daytime heating of the moistening boundary layer will

permit 1000 to 1500 J/kg CAPE to evolve, leading to the development

of thunderstorms along the advancing front -- first across western

Nebraska, and then shifting southeastward with time.  Isolated

storms may also develop separately across eastern Colorado,

eventually congealing into a larger convective cluster/system that

is expected to move across Nebraska and Kansas through the evening.



With shear sufficient for supercells, but a rather deep mixed layer

anticipated, primary risk should be locally damaging wind gusts, as

well as hail in the 1 to 1.75" range with the strongest storms. 

With upscale growth expected however, risk should favor damaging

wind gusts overall.  While storms will likely continue through the

overnight period, shifting into/across the Mid-Missouri Valley

region, severe threat should eventually diminish due to nocturnal

boundary-layer stabilization.



..Goss/Wendt.. 05/03/2024



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