ACUS01 KWNS 251631 SWODY1 SPC AC 251630 Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1130 AM CDT Sun Aug 25 2024 Valid 251630Z - 261200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE NORTHERN PLAINS/UPPER MIDWEST AND CENTRAL ROCKIES... ...SUMMARY... Severe wind gusts and hail are most probable today over parts of the Four Corners to southwestern Wyoming, and this evening over portions of the eastern Dakotas and western Minnesota. ...Northern Plains/Upper Midwest... Scattered thunderstorms are expected to develop along/ahead of the cold front and near a South Dakota surface wave, primarily this evening after 00Z/7pm CDT, although enough moistening and heating may occur for isolated late-afternoon development. Some supercells and bowing lines/clusters are expected, with large hail and severe wind gusts possible. Intensifying thunderstorm development should occur as the front encounters what is left of a diurnally well-heated and still-unstable boundary-layer airmass. Forecast soundings indicate the moist layer should deepen through the day beneath strong capping and steep mid-level lapse rates, MLCAPE in the 3000-4000 J/kg range possible. This will occur with gradually strengthening west-southwesterly winds aloft with 30-45 kt effective shear. Additional severe storms may occur late this afternoon into evening within an evolving post-frontal environment across northeast Wyoming into northwest South Dakota/southwest North Dakota, with moderate buoyancy and very long/straight hodographs potentially supporting storms capable of hail and possibly severe-caliber wind gusts. ...Central/southern Rockies... Scattered thunderstorms are ongoing early today across eastern Utah and western Colorado in advance of an upper-level trough centered over Nevada. A greater coverage and intensity of storms should occur into the afternoon as the boundary layer further warms/destabilizes. Relatively strong mid/high-level southwesterlies will support ample deep-layer/effective shear, with supercells and bowing clusters possible in a corridor spanning portions of the Four Corners area to northern Colorado/southwest Wyoming. Elongated and semi-straight hodographs will support large-hail potential aside from a broader regional risk for severe-caliber wind gusts. ...South-central High Plains... Scattered slow-moving thunderstorms are expected this afternoon particularly across eastern Colorado and northeast New Mexico. Hot/well-mixed boundary layers within the pre-convective environment will support the possibility of strong to locally severe-caliber wind gusts through late afternoon until around sunset. ..Guyer/Wendt.. 08/25/2024 $$