Severe Storm Outlook Narrative (AC)
Issued by NWS
Issued by NWS
897 ACUS03 KWNS 170731 SWODY3 SPC AC 170730 Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0230 AM CDT Wed Jul 17 2024 Valid 191200Z - 201200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE NORTHERN AND CENTRAL HIGH PLAINS... ...SUMMARY... Isolated strong to severe thunderstorms are possible across portions of the northern and central High Plains on Friday. ...Synopsis and Discussion... Expansive upper ridging is expected to be in place from the Southwest into western Canada early Friday morning, with upper troughing anticipated east of this ridging across the central and eastern CONUS. This overall upper pattern is forecast to remain in place across the CONUS throughout the period. Surface pattern early Friday will be dominated by a strong high over the OH Valley, with a weak stationary front along its southern periphery stretching from SC into the TX Hill Country. Warm and moist conditions are expected along this boundary, and thunderstorm development is anticipated during the afternoon amid modest low-level convergence. Storm severity should be mitigated by weak shear and largely disorganized storm mode. At least modest low-level moisture will likely be in place along and east of the surface lee troughing anticipated across the High Plains. This moisture will enable airmass destabilization in the vicinity of the lee trough, despite warm low/mid-level temperatures. Low-level convergence is expected along the lee trough, with some additional ascent potentially provided by a low-amplitude shortwave trough currently expected to move through the northwesterly flow aloft over the northern High Plains. Combination of these factors may result in thunderstorm development within the moderately buoyant and sheared airmass, suggesting some updraft organization is possible. An outflow-dominant storm character is likely, with damaging gusts as the primary severe risk. Some isolated large hail is possible within any more cellular development. ..Mosier.. 07/17/2024 $$