Severe Storm Outlook Narrative (AC)
Issued by NWS
Issued by NWS
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720 ACUS01 KWNS 210045 SWODY1 SPC AC 210043 Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0743 PM CDT Fri Sep 20 2024 Valid 210100Z - 211200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE CENTRAL PLAINS REGION AND OVER THE NORTHERN HIGH PLAINS... ...SUMMARY... Isolated strong to severe thunderstorms remain possible across parts of the central Plains region and the northern High Plains. ...01z Update... Early-evening water-vapor imagery depicts a stubborn upper anticyclone positioned over TX. There is some indication a weak disturbance is flattening the height field a bit over KS, per an elongated cluster of robust convection that extends from west of CNK-SLN-west of ICT. 00z sounding from TOP exhibits seasonally low PW value (1.12 in), but ample 0-6km bulk shear for organized updrafts (40kt). Lower-tropospheric RH is fairly low which may be contributing to strong wind gusts that have been reported with this activity. Until the boundary layer cools later this evening there may be a propensity for locally severe winds with the broken squall line. While LLJ is not expected to be particularly strong, some strengthening in the LLJ is expected over the next few hours across eastern KS and this may allow convection to maintain some intensity through the mid-evening hours. A few strong gusts may also be noted with convection as it spreads east-southeast across northeast MT over the next few hours. 00z sounding from GGW is strongly sheared and lapse rates are steep. While the most robust updrafts are lagging the main wind shift, left exit region of 70kt 500mb jet will translate across this region. Large-scale should contribute to some longevity with this activity as it propagates toward northwest ND. ..Darrow.. 09/21/2024 $$