SPC Jun 27, 2025 2000 UTC Day 1 Convective Outlook
SPC 2000Z Day 1 Outlook


Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0300 PM CDT Fri Jun 27 2025

Valid 272000Z - 281200Z

...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
CENTRAL NORTH DAKOTA...

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM NORTHERN
INDIANA INTO SOUTHEAST LOWER MICHIGAN...

...SUMMARY...
Scattered thunderstorms are expected late this afternoon/evening
across the Dakotas and Nebraska, where very large hail, severe
outflow winds, and a few tornadoes will be possible. Occasional
wind damage will be possible this afternoon from northern Indiana
into southeast Lower Michigan.

...20Z Update...
The primary change with this update was the addition of an Enhanced
risk over parts of central ND -- driven by 30-percent hail
probabilities. Based on the latest high-resolution guidance and
observations, confidence has increased that several semi-discrete
supercells capable of producing very large hail will evolve along
the northern periphery of strong to extreme surface-based buoyancy
and very favorable deep-layer shear into tonight. Elsewhere, only
minor changes were made to the outlook. For information on the
severe risk in Lower MI and northern IN, reference Severe
Thunderstorm Watch 466.

..Weinman.. 06/27/2025

.PREV DISCUSSION... /ISSUED 1114 AM CDT Fri Jun 27 2025/

...Dakotas/NE/MN...
Water vapor imagery shows a fast-moving shortwave trough moving
across MT. As this feature overspreads the northern Plains this
afternoon/evening, scattered thunderstorm development is expected
from western ND into central/western SD. Storms will track
southeastward in a moist and very unstable air mass, where steep
mid-level lapse rates and sufficient vertical shear will support the
development of supercells. Very large hail and a few tornadoes are
possible with this early activity. Congealing outflows after dark
may result in one or more bowing segments capable of severe wind
gusts. Have expanded the SLGT a little farther east into MN to
account for various morning CAM solutions.

...Lower MI...
Visible satellite imagery shows clear skies from northern IN into
southeast Lower MI, with dewpoints in the 70s and afternoon CAPE
values expected in the 2000-3000 J/kg range. A weak shortwave
trough will pass to the north of this area, providing weak lift and
aiding in thunderstorm development by mid afternoon. Steep
low-level lapse rates will promote a risk of damaging wind gusts in
the stronger cells.

...East TN/north GA...
Another active day of scattered thunderstorms is expected, with
hot/humid conditions aiding in the risk of locally damaging wind
gusts and some hail in the stronger cells.


Read more
https://www.spc.noaa.gov/products/outlook/day1otlk_2000.html