Subj : DAY2SVR: Nws Storm Prediction Center Norman Ok To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Mon Aug 12 2024 17:32:29 ACUS02 KWNS 121732 SWODY2 SPC AC 121730 Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1230 PM CDT Mon Aug 12 2024 Valid 131200Z - 141200Z ....THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS IN PARTS OF THE GREAT BASIN INTO THE NORTHERN/CENTRAL ROCKIES AND ADJACENT HIGH PLAINS AND ACROSS SOUTHERN NEBRASKA AND NORTHERN KANSAS TO NORTHWEST MISSOURI...AND ACROSS MUCH OF CENTRAL AND EASTERN SOUTH CAROLINA... ....SUMMARY... Isolated severe thunderstorms are possible Tuesday across parts of the eastern Great Basin into the northern/central High Plains and central Plains, as well as portions of South Carolina and vicinity. ....Synopsis... On Tuesday, the larger-scale pattern will feature a mid-level trough on the West Coast with a ridge across the central CONUS and a positively tilted trough along the east coast. This pattern will shift east with the mid-level ridge strengthening through the period. However, despite the strengthening ridge, some weak mid-level perturbations within the flow will likely be a catalyst for thunderstorm development from eastern Colorado, across the Plains, and into northwest Missouri Tuesday night. ....Eastern Great Basin to the Northern/Central High Plains... Broad height falls ahead of a mid-level shortwave trough moving from the Great Basin to the Northern Rockies will lead to widespread thunderstorm development on Tuesday. The greatest instability, and thus potential for more robust updrafts will exist from eastern Utah into eastern Idaho and western Wyoming. 35 to 40 knots of shear should be sufficient for a few supercells capable of large hail in this region. Elsewhere, severe-wind gusts will be the primary threat amid high-based convection promoting strong downdraft production. An additional area of focused convection will exist across eastern Colorado into eastern Wyoming and the Nebraska Panhandle. Convection will first develop across the higher terrain before into moderate instability across the Plains. Mid-level flow will be relatively weak closer to the ridge axis, but 50 knot southwesterly flow is forecast above 400mb which should help organize the stronger storms and lead to a threat for some supercells capable of large hail and severe wind gusts. There is a consistent signal that storms may congeal into a MCS across northeast Colorado and move across southern Nebraska during the overnight period. The strengthening low-level jet should maintain this MCS and forecast soundings show sufficient instability/shear for some isolated severe threat during the overnight period. ....South Carolina... A cold front will linger across South Carolina on Tuesday with mid 70s dewpoints south of it. This will allow for moderate destabilization ahead of a mid-level shortwave trough which will approach during the day. Warm mid-level temperatures and thus, weak mid-level lapse rates will be the primary limiting factor for severe storms. However, there will be sufficient instability 1000-2000 J/kg and moderate shear 40-45 knots which may allow for isolated strong to severe storms. Given the warm temperatures aloft, the primary threat will be damaging wind. ....Southeast Nebraska/northeast Kansas into northwest Missouri... Tuesday night, a low-level jet will strengthen to 40 to 45 knots across the central Plains amid a very moist environment. As isentropic ascent increases early Wednesday morning, MUCAPE will increase to near 3000 J/kg. Westerly effective shear is forecast around 35 knots which will be sufficient for some storm organization including the potential for a few supercell structures. While heavy rain will likely be the primary threat, some large hail or severe wind may be possible. ...Bentley.. 08/12/2024 $$ = = = To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM. --- SBBSecho 3.20-Linux * Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105) .