Subj : DAY3SVR: Nws Storm Prediction Center Norman Ok To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Tue Mar 19 2024 07:30:42 ACUS03 KWNS 190730 SWODY3 SPC AC 190729 Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0229 AM CDT Tue Mar 19 2024 Valid 211200Z - 221200Z ....THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS THURSDAY INTO THURSDAY EVENING ACORSS PARTS OF CENTRAL AND SOUTHEAST TEXAS...ADJACENT SOUTHWESTERN LOUISIANA... ....SUMMARY... Strong thunderstorms may impact parts of central and southeast Texas into adjacent portions of southwestern Louisiana on Thursday. One or two organizing clusters could evolve, accompanied by at least some risk for severe hail and wind. ....Synopsis... It appears that split westerlies will continue to trend more zonal to the east of the Rockies during this period, in the wake of a deepening and occluding cyclone migrating northeastward across the Canadian Maritimes. Models suggest that the leading edge of a significant cold intrusion trailing the cyclone will stall across the southern Mid Atlantic, and perhaps substantively begin to modify across the Tennessee Valley and Ozark Plateau into the lower Ohio and Missouri Valleys. Across the Great Plains, some of this cold air may continue to nose southward toward the Texas South Plains, in the wake of mid-level troughing progressing east of the southern Rockies/northern Mexican Plateau toward the lower Mississippi Valley/northwestern Gulf of Mexico. Although substantive spread is evident in the various model output concerning a couple of smaller-scale embedded perturbations, it appears that one mid-level cyclonic vorticity center will weaken while progressing east-southeast of the Texas Panhandle vicinity early the period. A trailing perturbation may become better-defined while progressing east of the Permian Basin/Texas Bend through the upper Texas coast vicinity by late Thursday night. Models suggest that this could support a developing surface low across the upper Texas coastal plain/northwestern Gulf coast vicinity, along the western flank of a developing frontal zone extending east-southeastward into the southeastern Gulf of Mexico. However, it still appears that any cyclogenesis will be rather weak. ....Southeast Texas... Moderate boundary-layer CAPE developing beneath warm and capping elevated mixed-layer air may spread north-northwest of middle Texas coastal areas, toward the Interstate 35 corridor of central Texas during the day. This may be aided by a corridor of stronger daytime heating, but much will depend on the extent of convective development which may be spreading east-northeastward into middle Texas coastal areas at the outset of the period, supported by forcing for ascent associated with a perturbation emanating from the subtropical eastern Pacific. There is some signal in the model output that this activity could grow upscale, supported by increasingly moist/unstable low-level inflow, while progressing across the coastal plain into the western Gulf of Mexico. If this occurs, potential for renewed vigorous thunderstorm later in the day across parts of central into southeast Texas becomes more unclear. Barring a substantive negative impact on further inland destabilization, forcing for ascent with the primary upstream short wave may contribute to the initiation of scattered thunderstorm activity by late afternoon. In the presence of strong deep-layer shear, supercells capable of producing large hail and locally damaging wind gusts will be possible. Although low-level hodographs may be modest to weak, a tornado or two will probably also be possible. Into Thursday evening, convection may tend to consolidate and grow upscale into an organizing cluster near or just ahead of the developing surface low across upper Texas into southwestern Louisiana coastal areas. It is possible that severe probabilities across at least parts of upper Texas coastal areas will need to be increased in later outlooks. However, this may take a few cycles with much depending on sub-synoptic developments. ...Kerr.. 03/19/2024 $$ = = = 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) .