Subj : DAY1SVR: Day 1 Convective Outlook To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Tue Jun 20 2023 16:26:10 ACUS01 KWNS 201626 SWODY1 SPC AC 201624 Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1124 AM CDT Tue Jun 20 2023 Valid 201630Z - 211200Z ....THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER PARTS OF LOUISIANA AND EAST TEXAS...AND OVER PORTIONS OF EASTERN MONTANA AND THE DAKOTAS.... ....SUMMARY... Isolated to scattered severe thunderstorms appear possible today across parts of the northern Plains, and east Texas to the Southeast. Damaging winds and large hail should be the main threats. ....LA/TX... Morning water vapor imagery shows a dominant ridge aloft extending from the southern Plains into the upper Midwest, with a band of relatively fast northwesterly mid-level flow from MO/AR into LA/MS. An extremely moist low-level air mass is present beneath the southwesterly fringe of the strong winds aloft, with dewpoints in the upper 70s to near 80F over parts of east TX and much of LA. Strong heating will yield very large CAPE values this afternoon and promote scattered thunderstorm development. Storms will mainly develop along/ahead of a southwestward sagging surface boundary that currently extends from northern LA into southern MS. A few of the cells will likely be severe, with hail and damaging winds possible through the evening. ....SD/ND... A weak surface cold front currently extends from north central ND into southeast SD. Substantial low-level moisture along and east of the front, coupled with full sunshine, will result in moderate CAPE by afternoon. Large scale forcing for ascent associated with a shortwave trough currently over northwest CO will overspread the area this afternoon, promoting scattered thunderstorms along the front. Low-level winds are relatively weak, but sufficient deep layer shear will promote organized multicell or a few supercell storms capable of large hail and damaging winds. ....Eastern MT/western ND... Model guidance shows a well-defined 60-70kt mid-level jet over northern NV. Forcing associated with this feature is moving across western WY and is expected to result in a scattered thunderstorms over the Big Horn mountains by mid-afternoon. These storms will track northeastward into southeast MT and eventually western ND tonight. A cluster of fast-moving supercells or bowing structures (similar to yesterday) is possible, capable of damaging winds and hail. ...Hart/Squitieri.. 06/20/2023 $$ = = = 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 3.14-Linux * Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105) .