SPC Jun 26, 2025 0100 UTC Day 1 Convective Outlook

SPC 0100Z Day 1 Outlook

Day 1 Convective Outlook  
NWS Storm Prediction Center Norman OK
0804 PM CDT Wed Jun 25 2025

Valid 260100Z - 261200Z

...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS THROUGH EARLY
TONIGHT FOR PARTS OF SOUTH CAROLINA AND EASTERN GEORGIA...

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS THROUGH LATE
EVENING FOR A SMALL AREA AROUND SOUTHWEST WISCONSIN...AND INTO
TONIGHT FROM SOUTH CAROLINA INTO SOUTHERN ALABAMA...

...SUMMARY...
Damaging outflow gusts and isolated large hail will remain possible
for the next several hours from South Carolina to southern Alabama. 
A couple of tornadoes will be possible in the short term in the
vicinity of southwest Wisconsin.

...Southeast tonight...
Clusters of storms are ongoing across SC, where outflow mergers have
led to consolidation of a cold pool.  The storms will likely persist
for several more hours while spreading southwestward over the
coastal plains of SC/GA, sustained by steeper-than-usual midlevel
lapse rates and strong buoyancy.  Isolated large hail of 1-1.5
inches in diameter will remain a possibility with the stronger
embedded storms (especially with mergers), but damaging outflow
gusts will be the main threat with collapsing cores in the steep
lapse rate environment with strong downdraft potential (as suggested
by DCAPE of 1000-1500 J/kg).

Farther southwest, a few strong-severe storms will be possible
through about 02-03z along the conglomerate outflow from southwest
GA into southern AL.

...Southwest WI/southeast MN/northeast IA this evening...
Several tornadoes have been reported with supercells in a broken
band from northeast IA across far southeast MN into southwest WI. 
These storms have trended toward a more linear mode over time and
the tornado threat appears to have already peaked.  Prior to the
storms weakening early tonight, the potential for a couple of
tornadoes will persist for another 1-2 hours with the stronger
embedded supercells interacting with the warm front, where low-level
hodograph curvature/shear are maximized.

...Eastern NE/western IA this evening...
Convection has been largely undercut by convective outflow from
eastern NE into western IA.  Moderate buoyancy remains immediately
to the south of the aggregate outflow/effective frontal boundary,
and profiles will remain sufficiently moist to maintain elevated
convection into the overnight hours.  However, the potential for
severe storms appears to be diminishing with time, with only
isolated strong outflow gusts and/or marginally severe hail expected
beyond 01z.

...Northern High Plains through early tonight...
Widely scattered storms, some with supercell structure, will be
possible through about 03z.  Thereafter, convection is expected to
weaken consistently with diurnal stabilization.  In the interim,
isolated large hail of 1-1.5 inches in diameter will be possible.

..Thompson.. 06/26/2025

StormPrep