Subj : DAY1SVR: Day 1 Convective Outlook To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Mon Dec 30 2024 19:42:26 ACUS01 KWNS 301942 SWODY1 SPC AC 301941 Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0141 PM CST Mon Dec 30 2024 Valid 302000Z - 311200Z ....NO SEVERE THUNDERSTORM AREAS FORECAST... ....SUMMARY... Severe thunderstorms are not expected through tonight. ....20z Update... The previous forecast remains on track with no changes required. Latest guidance continues to suggest that a swath of weak thunderstorms will overspread the OH River Valley late tonight into early Tuesday morning. Some solutions, notably recent runs of the HRRR and RAP, hint that a corridor of surface-based convection may develop from northwest KY/southern IN into north-central KY/southwest OH between 07-12 UTC along the primary surface trough. SBCAPE/lifted indices will remain fairly limited (250-500 J/kg and -1 to -2 C respectively) and modulate overall convective intensity; however, 40 knot, nearly uni-directional flow within the 0-1 km layer may promote sporadic damaging wind gusts during the pre-dawn hours. Consideration was given for 5% wind probabilities, but the overall convective signal in recent guidance remains too limited to garner sufficient confidence in this potential threat. ...Moore.. 12/30/2024 ..PREV DISCUSSION... /ISSUED 1022 AM CST Mon Dec 30 2024/ ....OH Valley tonight... An 80-100 knot mid-level jet max will move quickly eastward across the central Plains today, and into the mid MS Valley tonight. Strong cyclogenesis will occur in advance of this system over MO/IL, with the primary baroclinic zone sweeping across AR into KY/TN. Strengthening southerly low-level winds in the warm sector of the deepening low will result in broad low-level warm/moist advection, and perhaps just enough CAPE for a few thunderstorms late tonight across the lower and middle OH Valley. Forecast soundings show impressive low-level shear profiles, but thermodynamics are quite weak with surface-based convection unlikely. Thus the severe threat is low. $$ = = = 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) .