Severe Storm Outlook Narrative (AC)
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121
ACUS02 KWNS 010557
SWODY2
SPC AC 010556

Day 2 Convective Outlook
NWS Storm Prediction Center Norman OK
1256 AM CDT Tue Jul 01 2025

Valid 021200Z - 031200Z

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM EASTERN
OREGON TO NORTHERN MONTANA AND FAR NORTHWEST NORTH DAKOTA AND FROM
THE UPPER MIDWEST TO THE CENTRAL GREAT LAKES....

...SUMMARY...
At least scattered storms are possible across a large portion of the
continental U.S. on Wednesday. A couple of severe gusts may
accompany the stronger storms over portions of the Northern Rockies
and the Upper Midwest to central Michigan region.

...Synopsis...
A ridge centered across the northern Plains will drift slowly east
through the period. To the east of this ridge, a mid-level trough
and associated jet streak will dig into the Great Lakes. To the west
of this ridge, several embedded shortwave troughs are forecast
within moderate southwesterly flow.

...Eastern Oregon to northern Montana and far northwest North
Dakota...
Scattered thunderstorms are forecast within a zone of steep
low/mid-level lapse rates from eastern Oregon into much of Montana.
Effective shear of 25 to 30 knots will support some storm
maintenance/organization including the potential for multicell
clusters. A hot and well-mixed boundary layer featuring 40-50F
dewpoint depressions will support some threat for isolated severe
wind gusts from this activity. However, weak instability should
limit a greater severe weather threat.

...Upper Midwest across Lake Michigan and much of central/northern
Lower Michigan...
Elevated thunderstorms may be ongoing at the beginning of the period
across eastern South Dakota/western Iowa on the nose of the
low-level jet. This activity should weaken during the morning. Weak
to moderate instability is forecast do develop during the afternoon
from the Upper Midwest to northern/central Lower Michigan. A weak
mid-level shortwave trough is forecast to move southeastward across
this region Wednesday afternoon. As this occurs, isolated to
potentially scattered thunderstorms are possible. 35 to 40 knots of
mid-level flow may support some storm organization, including the
potential for transient supercells. Isolated large hail and damaging
wind gusts will be the primary threat.

..Bentley.. 07/01/2025

$$