Subj : DAY1SVR: Day 1 Convective To : All From : Mike Powell Date : Thu Jun 01 2023 15:58:00 ACUS01 KWNS 012002 SWODY1 SPC AC 012000 Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0300 PM CDT Thu Jun 01 2023 Valid 012000Z - 021200Z ....THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE SOUTHERN HIGH PLAINS... ....SUMMARY... Large hail along with a severe wind/tornado risk will remain focused across far eastern New Mexico and west Texas late this afternoon and evening. ....20Z Update... Some adjustments have been made to the severe probabilities across the southern High Plains, based on recent observational trends regarding the position of an outflow boundary and the movement of a small semi-organized storm cluster across parts of the TX South Plains. Some threat for localized severe hail/wind cannot be ruled out with the ongoing storm cluster as it moves eastward through the remainder of the afternoon, with some modest destabilization noted downstream. Along the trailing outflow, at least isolated development will be possible, given that some recovery is occurring in the wake of earlier convection. Any supercell that can move east-southeastward along the outflow later this afternoon and evening would pose a conditional risk for all severe hazards. Elsewhere, no changes have been made. See the previous discussion below for more information. ...Dean.. 06/01/2023 ..PREV DISCUSSION... /ISSUED 1138 AM CDT Thu Jun 01 2023/ ....Southern High Plains including Eastern NM/West TX... Key mesoscale factors for severe-weather potential later today are a composite outflow boundary and zone of differential heating/baroclinicity that extends roughly west-east across southeast New Mexico and the Texas South Plains. Convection continues to redevelop into midday and reinforce the aggregate/primary boundary across the aforementioned corridor, casting uncertainty/doubts on more northward-aggressive (with respect to boundary/destabilization) guidance such as the 12z NAM. Regardless, satellite/surface observations and related trends imply that ample heating will occur to the west/south of this boundary within an air mass that continues to remain rather moist (upper-end of daily climatological values). The strongest destabilization is expected to occur across the Texas South Plains and far southeast New Mexico, which is where severe potential later today is expected to be maximized in vicinity of the modifying outflow boundary. Owing to moderately strong mid-level southwesterly winds (and considerably stronger high-level winds), wind profiles will be supportive of initial supercells capable of large hail. At least some tornado potential will be semi-focused in vicinity of the modifying boundary, although low-level winds are not expected to be overly strong, which should tend to limit the overall tornado likelihood and risk magnitude. Storms may again cluster with a somewhat localized but increasing potential for severe-caliber winds by early evening, potentially toward parts of the Texas Low Rolling Plains. Farther to the northwest, somewhat more modest, but potentially severe-conducive, destabilization is expected as far northwest as east-central/northeast New Mexico, with isolated instances of severe hail as the most probable hazard this afternoon and early evening. ....North-central High Plains... Isolated to scattered thunderstorms are expected this afternoon into early evening, near the dryline/lee trough, from near I-80 northward over the Nebraska Panhandle and eastern Wyoming toward the Black Hills vicinity. This activity may be associated with a corridor of relatively maximized large-scale ascent aloft, ahead of a minor shortwave trough ejecting northward out of northern Colorado. Although mid/upper-level lapse rates will be seasonally modest over this region, surface dewpoints in the mid 40s to mid 50s F may support pockets of 1000-1500 J/kg MLCAPE. Weak low-level/deep-layer shear are forecast, but isolated instances of severe hail and/or severe-caliber wind gusts are possible. $$ --- SBBSecho 3.14-Linux * Origin: Ilink: CCO - capitolcityonline.net (454:1/105) .