Severe Storm Outlook Narrative (AC)
Issued by NWS
Issued by NWS
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427 ACUS01 KWNS 160541 SWODY1 SPC AC 160540 Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1240 AM CDT Sun Jun 16 2024 Valid 161200Z - 171200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE NORTHERN/CENTRAL PLAINS INTO THE UPPER GREAT LAKES... ...SUMMARY... Scattered strong to severe storms are expected this evening and overnight from parts of the northern Plains into the upper Mississippi Valley, with hail the primary risk. ...Northern/Central Plains to the upper Great Lakes... Northern Rockies short-wave trough will eject northeast across SK/MB into western ON by 17/00z. This feature is expected to partially influence the upper Great Lakes region, with only weak height falls glancing northern portions of MN. Otherwise, the primary concern for the upper Great Lakes will be the early-day short-wave trough that will eject across WI/MI. This feature is currently located over western IA but convection has weakened considerably despite the large-scale support. Current thinking is non-severe convection should spread northeast across WI into the U.P. of MI early within a warm advection corridor. Weak short-wave ridging will be noted across much of the upper MS Valley in the wake of the early-day feature. The boundary that surges across MN, arcing back into the central Plains will provide a focus for low-level convergence; however, boundary-layer heating may be inadequate for appreciable surface-based convection until late in the day. Latest models are not aggressive in developing convection along the boundary, but rather generate elevated convection north of the wind shift later in the evening as the LLJ refocuses over the central Plains after sunset. A strong signal for robust elevated convection exists across portions of SD/NE during the latter half of the period, and this activity should spread northeast during the overnight hours. Forecast soundings exhibit substantial MUCAPE (in excess of 2000 J/kg), if lifting parcels above 850mb within the strengthening warm-advection zone. Hail should be the primary concern with the elevated convection. ..Darrow/Thornton.. 06/16/2024 $$