Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0254 PM CDT Tue Aug 05 2025
Valid 052000Z - 061200Z
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR THE DAKOTAS...
...SUMMARY...
Scattered severe thunderstorms with an accompanying risk for large
hail, severe wind gusts, and perhaps a couple of tornadoes will be
possible this afternoon through much of the evening across the
Dakotas.
...20z Update...
No changes were made to the D1 Convective Outlook.
Air mass recovery trends continue to be monitored across the Dakotas
in the wake of morning convection. Breaks in the cloud cover have
led to heating across central/western South Dakota to the southern
North Dakota line. Warm moist air continues to spread northward
south of the differential heating boundary located across southern
ND into central SD. It appears that redevelopment/re-intensification
of thunderstorm activity is likely through the afternoon as further
destabilization continues. See MCD#1890 for more detailed
information on expected storm evolution through the afternoon.
..Thornton.. 08/05/2025
.PREV DISCUSSION... /ISSUED 1128 AM CDT Tue Aug 05 2025/
...Northern Plains...
Visible-satellite/radar mosaic imagery late this morning shows a
cluster of sub-severe thunderstorms associated with a lead lobe of
mid-level ascent/MCV moving through the base of a larger-scale
trough centered over MT/Saskatchewan. Deleterious effects of
widespread cloud cover over far northern SD into ND will likely
hinder appreciable destabilization through the early afternoon.
However, earlier forecast thinking of a differential heating zone
becoming more focused along the ND-SD border to the east of a weak
cyclone will potentially become consequential for the severe risk
later this afternoon/evening.
A reservoir of adequately rich low-level moisture with dewpoints in
the mid-upper 60s deg F will likely protrude northward into southern
ND as the airmass destabilizes this afternoon. Cloud breaks will
contribute to moderate to strong buoyancy (1500-3500 J/kg MLCAPE) to
the south of more stable conditions likely being maintained
throughout the day near the Canadian border. Forecast soundings
show enlarged low-level hodographs by mid-late afternoon and into
the evening with a 40-kt southerly LLJ centered on SD.
Short-term model guidance indicates renewed storm development is
most likely east of the low along the differential heating zone with
this activity spreading east into more vorticity-rich air.
Seasonably large uncertainty remains regarding this forecast during
the 22-02z period in which peak severe may occur. Supercells
capable of all hazards will be possible before clusters evolve and
the propensity for cold pool coalescence becomes detrimental for the
supercell threat and wind becomes the primary hazard later this
evening. Considerable uncertainty exists overnight on the potential
evolution of a cluster and an incipient wind threat into parts of
the MO Valley and Upper Midwest.
Read more CHECK UPDATE ZOOM GRAPHIC
http://dlvr.it/TMKRtd
