Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1137 AM CDT Sat Jul 25 2026
Valid 251630Z - 261200Z
...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FOR CENTRAL
INTO EASTERN SOUTH DAKOTA...
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS IN CENTRAL AND
EASTERN MONTANA...
...SUMMARY...
Widespread severe gusts are possible across South Dakota late this
afternoon through the evening.
...SD into adjacent parts of IA/MN...
A prominent upper ridge centered over the central/southern Rockies
will feature the southern periphery of appreciably strong mid to
high-level flow extending from the Pacific Northwest across the
northern High Plains and into the north-central states. Late
morning surface analysis shows very hot temperatures ensuing across
western NE into the western half of SD with richer moisture (surface
dewpoints in the lower to mid 70s F) located over the eastern half
of NE/SD. Visible-satellite imagery shows some mid to high clouds
across northern WY moving towards the Black Hills. This patch of
clouds appears associated with a weak disturbance forecast to move
into western SD later this afternoon.
Downstream across SD, forecast soundings show very steep surface to
500-mb lapse rates developing as temperatures rise into the 100s F.
Expecting initially isolated to widely scattered storms to develop
near the Black Hills, as convective temperatures are breached.
Models show the gradual development of a cluster moving east across
SD early this evening. Have increased severe-wind probabilities to
account for observational and model-based trends towards an MCS
capable of peak gusts in the 75-90 mph range. This activity will
probably slowly weaken towards the MN/IA/SD border but perhaps
continue into early overnight with a wind threat.
...MT...
Isolated to scattered storms will likely form near the higher
terrain of southern MT later this afternoon with a gradual increase
in storm coverage as this moves east during the early evening. A
hot and well-mixed boundary layer will support severe gusts with the
stronger cores and associated outflow. There is some indication
this activity will cluster and potentially reach parts of
eastern/southeast MT by the late evening.
...Upper Midwest/Upper Great Lakes...
Conditional severe potential exists across parts of the Upper
Midwest spanning Minnesota to Upper Michigan into Wisconsin. Models
continue to show low storm chances as mid-level heights rise through
the late evening. Nonetheless, appreciable heating of a seasonably
moist boundary layer will result in strong potential buoyancy later
today into tonight. Elongated hodographs will support organized
storms capable of a wind/hail threat. Given a muted diurnal storm
signal in models, the greater chance for isolated storms appears to
be associated with warm advection activity late tonight.
...Northeast NV/northern UT/eastern ID...
Storm development is expected during the afternoon across parts of
northeast Nevada, along the western periphery of the upper ridge.
These storms will spread into adjacent parts of southeast Idaho and
northwest Utah with time. Isolated severe gusts may accompany the
stronger downdrafts.
...South-central/southeast AZ...
High-based convection is again expected across southeast Arizona
during the afternoon, with initial downburst potential. A modest
enhancement to easterly flow along the southern periphery of the
upper ridge may allow for localized strong to severe wind gusts to
spread westward into parts of south-central Arizona, before
convection weakens tonight.
..Smith/Moore.. 07/25/2026
Read more CHECK UPDATE ZOOM GRAPHIC
http://dlvr.it/TTjFwT
