ACUS01 KWNS 251242

SWODY1

SPC AC 251241



Day 1 Convective Outlook  

NWS Storm Prediction Center Norman OK

0741 AM CDT Sat Oct 25 2025



Valid 251300Z - 261200Z



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

TEXAS AND LOUISIANA...



...SUMMARY...

Scattered severe thunderstorms are possible today into tonight from

central Texas eastward into the lower Mississippi Valley.



...TX-LA...

Water-vapor imagery shows a mid- to upper-level low over the

southern High Plains and it is forecast to move east across much of

OK by early Sunday morning.  Strong cyclonic 500-mb flow (40-60 kt)

will move through the base of the larger scale trough over TX and

eventually moving into the lower MS Valley.  An ongoing MCS across

southwestern LA and the northwest Gulf of America will likely

progress eastward across southern LA through early afternoon.  An

isolated risk for damaging gusts (55-65 mph) and a brief tornado may

continue east but be increasingly confined to the coastal parishes

as the squall line's eastward movement outpaces appreciable inland

destabilization.  



High uncertainty is apparent farther west across central into east

and coastal portions of TX.  Earlier shower/thunderstorm activity

across much of the mid and upper coastal plain of TX has rendered

substantial convective overturning of the airmass from the coastal

plain northwestward towards the I-35 corridor north of a composite

outflow boundary.  Models vary regarding destabilization and this

signal in model data is congruent with forecaster experience in

placing low confidence in potential storm evolution later this

afternoon into the evening across central and east TX.  Nonetheless,

there will probably exist a window of opportunity for diurnal

destabilization arcing around the south and west portions of the

mesoscale surface high.  Some forecast soundings show moderate

instability in the presence of strong mid to high-level westerly

flow---supporting supercells and storm organization with

accompanying potential for damaging gusts.  



Have adjusted the northern bounds of tornado probabilities farther

south in closer proximity to richer moisture, and removed 15-percent

hail probabilities across southeast TX and LA where lapse rates will

likely remain stunted through early Sunday morning.  The tornado

risk correspondingly will tend to favor any supercell development in

proximity to richer moisture and mesovortex structures within parent

QLCSs, but low confidence exists regarding this forecast given

aforementioned convective-related concerns.  



...Pacific Northwest...

A mid-level trough, and an associated plume of moisture, will move

eastward into the Pacific Northwest today.  Strong large-scale

ascent will be favorable for thunderstorm development along the

coast of Washington and Oregon.  A brief tornado risk could develop

near the immediate coast and marginally severe wind gusts will be

possible as cells move inland.  Farther east into parts of southeast

Washington and far northeast Oregon, thunderstorm development will

be possible late this afternoon with perhaps isolated severe gusts

associated with the stronger thunderstorms.



..Smith/Weinman.. 10/25/2025



$$