036
ACUS48 KWNS 240839
SWOD48
SPC AC 240837

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0337 AM CDT Fri Jul 24 2026

Valid 271200Z - 011200Z

...DISCUSSION...
...Day 4/Monday...
A prominent upper high will remain centered over the central and
southern Plains with a belt of enhanced mid-level flow forecast
along the periphery of that feature from the northern Plains into
the Great Lakes. Within that flow regime, a short-wave trough is
forecast to translate through the Great Lakes in tandem with a
surface low and trailing cold front. A hot and moist boundary layer
is expected ahead of the front, yielding moderate to strong
instability by afternoon. Despite veered low-level winds,
strengthening mid/upper-level winds in the exit region of a jet
streak will contribute to sufficient vertical shear for organized
severe storms across portions of the Great Lakes into the OH Valley
Monday afternoon into night.


...Day 5/Tuesday...
The Day 4/Monday short-wave trough is forecast to evolve into an
upper low across southwest ON and the lower Great Lakes with an
associated belt of stronger cyclonic flow developing from the OH
Valley into the southern Mid-Atlantic and NC. At the surface, an
area of low pressure will develop from the lower Great Lakes into
central NY with a trailing cold front advancing through the upper OH
Valley, central Appalachians, and Mid-Atlantic.

Thunderstorms may be ongoing Tuesday morning along and ahead of the
front from the lower Great Lakes and upper OH Valley into the
Mid-Atlantic. Stronger heating is anticipated to the south of the
early-day storms from the southern Mid-Atlantic into NC, where
moderate to potentially strong instability is forecast. The
strongest instability will coincide with modestly strong deep-layer
shear to support some severe weather threat in those areas Tuesday
afternoon and evening.


...Days 6-8/Wednesday-Friday...
The 00Z ensemble means depict a slight westward regression of the
dominant mid/upper-level high with persistent troughing along the
East Coast. On the periphery of the high, a notable short-wave
trough is forecast to progress from the Canadian Rockies on
Wednesday through the Prairie Provinces on Thursday with modest
height falls along the international border. By Friday, there is
some model signal for another short-wave trough to move into the
upper MS Valley and Great Lakes regions. At the surface, a more
substantial cold front is projected to move into the northern Plains
on Thursday, and the upper Midwest and Great Lakes by Friday.

A few severe storms appear possible in the Southeast and northern
Plains on Wednesday, the northern Plains on Thursday, and the upper
Midwest into the Great Lakes on Friday. Confidence in the magnitude
and areal extent of the threat is currently too low to delineate
additional areas.

..Mead.. 07/24/2026