ACUS48 KWNS 100830
SWOD48
SPC AC 100828

Day 4-8 Convective Outlook  
NWS Storm Prediction Center Norman OK
0328 AM CDT Fri Apr 10 2026

Valid 131200Z - 181200Z

...DISCUSSION...
...Days 4-6/Mon-Wed -- Central/Southern Plains to the Midwest...

There is quite a bit of uncertainty regarding severe
potential/evolution during the Monday-Wednesday period. An upper
trough will slowly pivot across the West on Monday, and emerge over
the central/southern Rockies by early Wednesday before finally
ejecting across the Plains and toward the Mid/Upper MS Valley on
Wednesday. During this time, broad southwesterly deep-layer flow
will overspread the Plains into the Mid/Upper MS Valley. 

On Monday, a surface low will develop over the northern/central
Plains, with a dryline extending southward across KS/OK/TX and a
warm front extending across southern MN/WI. Several lead shortwave
impulses will move across the Plains, though height tendencies will
remain mostly neutral. Nevertheless, cooling aloft will support
steep midlevel lapse rates and increasing boundary layer moisture
(surface dewpoints in the low/mid 60s F) will support moderate to
strong destabilization. During the evening, a southwesterly
low-level jet will increase across the Plains, overspreading the
surface dryline. Vertically veering wind profiles and 30-40 kt
effective shear magnitudes would support supercells capable of all
hazards, though storm coverage remains uncertain.

By Tuesday, the GFS becomes more progressive with the western
trough, ejecting it into the Plains by early Wednesday, whereas the
ECMWF hangs the trough back west and is slower. Nevertheless, a
similar airmass will be in place across the warm sector east of a
dryline across the Plains and to the south of a warm front draped
across the Great Lakes. Isolated convection may develop along the
dryline across the Plains, posing a supercell/all-hazards risk.
Higher storm coverage appears more likely across portions of the
Mid/Upper MS Valley/Great Lakes vicinity closer to a surface low.

On Wednesday, the upper trough should progress from the Plains to
the Great Lakes while weakening some. A surface cold front will
develop southeast across portions of the central U.S. and some
severe risk should persist along/ahead of this boundary. How
convection evolves on Tuesday into Wednesday will impact where the
greatest severe risk will develop, but at least some risk should
exist from portions of the southern Plains to the Mid-MS Valley.

...Days 7-8/Thu-Fri...

Predictability is low heading into the end of the forecast period on
Thursday and Friday as large spread exists among medium range
guidance. However, western U.S. upper troughing may persist,
suggesting some severe thunderstorm potential could persist for
parts of the Plains late in the work week.

..Leitman.. 04/10/2026