Subj : DAY2SVR: Nws Storm Prediction Center Norman Ok To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Wed May 15 2024 17:28:48 ACUS02 KWNS 151728 SWODY2 SPC AC 151726 Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1226 PM CDT Wed May 15 2024 Valid 161200Z - 171200Z ....THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM WEST TX TO THE LOWER MS VALLEY... ....SUMMARY... Scattered severe thunderstorms are possible from west Texas to the Lower Mississippi Valley on Thursday afternoon into Thursday night. Very large hail, damaging winds, and a few tornadoes are likely. ...TX to the Lower MS Valley... Primary change this outlook has been to expand level 2-SLGT risk eastward for wind and tornado potential on Thursday evening/night from the Sabine to the Lower MS Valleys. Considered an upgrade to level 3-ENH risk for very large hail across the Permian Basin to Concho Valley, but enough uncertainty exists to defer to later outlooks. A southern-stream shortwave trough will progress east from the AZ/NM/northwest Mexico border area into the southern Great Plains on Thursday. Strong mid/upper-level flow will be displaced south of this wave across northern Mexico through most of TX. Early morning convection will likely be ongoing within the low-level warm theta-e advection regime focused along and north of a northeast to southwest-oriented cold front bisecting OK into west TX. While the low-level jet will subside after 12Z, large spread exists across guidance with the degree of warm-advection convection persisting into early afternoon. It is plausible that given a pronounced low-level moisture gradient persisting from southeast to north TX, renewed storm development may continue through the morning into the afternoon in parts of north and central TX. Outflows from this activity could yield an emerging MCS that spreads east-southeast in parts of central to southeast TX during the afternoon, while simultaneously impacting the most favorable corridor for upstream supercell development. This latter corridor should be focused in a mesoscale area be near the dryline/frontal intersection from the Permian Basin to Concho Valley vicinity. Conditionally, this area would favor potential for long-lived supercells with a vertical wind profile conducive to very large hail and a couple tornadoes. Eventual upscale growth from one or both regimes is likely amid both cold pool amalgamation and increasing large-scale ascent as the low-level jet further intensifies across the Sabine to Lower MS Valleys. A mix of damaging winds with a nocturnal tornado threat will be possible Thursday evening/night. ....Mid-MS Valley... A remnant MCV from a D1 MCS in parts of OK/KS should be a focus for renewed thunderstorm development on Thursday afternoon. Mid-level lapse rates will be weak near the MCV, but enhanced mid to lower-level flow should support a threat for a couple supercells capable of isolated severe. ....South FL... A weak baroclinic zone will sag south during the day. Morning convection may be ongoing along it with a marginally supportive environment for weak mid-level rotation. This activity should diminish, but renewed development may occur along the Atlantic coast sea breeze. Isolated, marginally severe wind and hail are possible. ....Western Great Lakes vicinity... With another day of warm/moist-sector modification, a few strong to marginally severe storms will be possible on Thursday afternoon ahead of a lower-amplitude shortwave trough and attendant surface front. Instability will still be limited, but moderate vertical shear could support a couple transient supercell structures around peak heating. ...Grams.. 05/15/2024 $$ = = = 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) .