Subj : DAY3SVR: Nws Storm Prediction Center Norman Ok To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Mon Feb 10 2025 19:22:28 ACUS03 KWNS 101922 SWODY3 SPC AC 101921 Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0121 PM CST Mon Feb 10 2025 Valid 121200Z - 131200Z ....THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM PARTS OF EASTERN LOUISIANA INTO CENTRAL/SOUTHERN MISSISSIPPI AND FAR WESTERN ALABAMA... ....SUMMARY... Severe storms will be possible Wednesday afternoon into Wednesday night from the Sabine Valley vicinity into far western Georgia. ....Lower MS Valley/Central Gulf Coast States... A large-scale upper trough will be located over the Plains/central U.S. Wednesday. A shortwave embedded within the larger-scale trough will rotated from the Plains to the Midwest/Great Lakes, resulting in a large swath of strong deep-layer southwesterly flow across the region. At the surface, low pressure will develop near the Sabine River during the morning, and deepen as the low lifts northeast through the period. Southerly low-level flow will maintain 60s F dewpoints across the Lower MS Valley and Gulf Coast states ahead of southeastward-advancing cold front. While widespread cloud cover and ongoing precipitation will limit stronger destabilization, and adds to uncertainty for this event, the overall large-scale pattern suggests some severe thunderstorm potential is likely from extreme southeast TX into MS/AL Wednesday afternoon into the overnight hours. Mid to upper 60s F dewpoints will approach the I-20 corridor by afternoon as the surface low develop northeast into TN/KY by 00z. Additionally, strong shear will overspread the region for much of the period (decreasing from west to east with time). Large-scale ascent will be somewhat offset to the north of the better low-level moisture, but a glancing influence coupled with the sharpening of the southeast-advancing cold front will be sufficient to sustain convection in a strong warm advection regime. Forecast soundings indicate enlarged low-level hodographs becoming elongated above 2-3 km, typical of supercell/QLCS environments and aided by a 45-60 kt low-level jet. However, low-level lapse rates are expected to remain poor given limited heating, and midlevel lapse rates also are expected to remain modest. MUCAPE around 500-1000 J/kg is evident in most forecast guidance, though surface-based instability is likely to remain muted. With shear vectors oriented parallel to the surface boundary, convection is likely to mostly be to the cool side of the boundary. However, given strength of shear and modest instability, some strong/severe wind potential is possible with organized line segments. While low-level lapse rates and instability are expected to remain poor, limiting overall tornado potential, a couple of mesovortex spin-ups within linear convection may still be possible given very favorable shear environment and any mesoscale pockets of greater instability. Currently, it is uncertain if convection will be able to develop ahead of the cold front in the open warm sector. Given the somewhat northward offset of stronger ascent and orientation of shear vectors to the initiating boundary, it appears low probability at this time that convection will be able to sufficiently deepen within the pre-frontal warm advection regime. However, if this occurs, a conditional risk for severe gusts and a couple of tornadoes with supercells will exist. The severe risk should gradually lessen overnight with north and east extent as instability decreases and large-scale ascent continues to lift to the northeast of the region. ...Leitman.. 02/10/2025 $$ = = = 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) .