####018001522####
ACUS48 KWNS 300852

SWOD48

SPC AC 300850



Day 4-8 Convective Outlook  

NWS Storm Prediction Center Norman OK

0350 AM CDT Tue Apr 30 2024



Valid 031200Z - 081200Z



...DISCUSSION...

Models are in good agreement on Friday/D4 showing an upper trough

lifting north out of the upper MS Valley and across western Ontario,

with a deep upper low moving south just off the coastal Pacific

Northwest. High pressure will exist over the Plains in the wake of

the northern trough, and is forecast to persist into Saturday/D5 as

a secondary lobe rotates the parent Ontario low. While a moist air

mass over the southern Plains and Gulf Coast will support

thunderstorms during this period, little organization or shear is

forecast. 



From Sunday/D6 onward, spread becomes large amongst the model

ensembles, especially in regard to the West Coast low and possible

trough amplification as it moves ashore. That said, the overarching

theme through D8 and perhaps beyond is for rising heights across the

East, and a mean trough across the West, which may eventually prove

favorable for moisture return, large-scale ascent and shear across

parts of the central CONUS. Some models such as the ECMWF suggest a

multi-day period of very strong to extreme instability, as well as

southwest flow aloft across the central and southern Plains toward

the MS Valley. While predictability is low that far out, the

evolution of this pattern will be watched closely.



..Jewell.. 04/30/2024