Subj : HVYRAIN: Excessive Rainfall Discussion To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Wed Jun 14 2023 07:55:26 FOUS30 KWBC 140755 QPFERD Excessive Rainfall Discussion NWS Weather Prediction Center College Park MD 354 AM EDT Wed Jun 14 2023 Day 1 Valid 01Z Wed Jun 14 2023 - 12Z Wed Jun 14 2023 ....THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF THE SOUTHEAST... ....Lower Mississippi Valley through the Southeast... Multiple rounds of heavy, organized activity is expected through tonight through much of MS/AL/GA as impulses and jet streaks shift east in flow parallel to the stalled frontal boundary over the Southeast. Ample Gulf moisture (PWs of 1.75 to 2") continues to pool along the frontal zone which will continue to meander north and south with the impulses given the instability pool along and north of the Gulf Coast. The westerly mean layer flow running parallel to the stationary fronts will support training and backbuilding convection over areas that are dealing with ongoing rounds of thunderstorms warranting further expansion of the Slight Risk to encompass the most likely heavy rain including areas farther south to the FL border where 1-2" fell yesterday. There remains a potential for the rounds tonight to focus over similar areas to this morning which could warrant a Moderate Risk upgrade. The risk of repeating activity roughly downstream of activity currently SW of Memphis warrants a northward expansion of the Marginal Risk into TN. ....Intermountain West and Northern Rockies onto the Northern Plains... An upper low pivoting over the Northern Rockies sends a cold front to the central portions of the Intermountain West and the renewed upper trough extending over southern CA send a surge of Pacific moisture up through this front. An axis of QPF with a risk for local 1"+ is forecast from the Sierra Nevada across the Great Basin to the CO Rockies in diurnally enhanced convection which continues to warrant a Marginal Risk. The cold front crosses the northern Rockies with lee-side convective activity in PW exceeding 1.25" by this evening (2 sigma above normal) over the already saturated central portions of Montana warrants maintenance of the Marginal Risk for much of Montana into the western Dakotas. Jackson Day 2 The Day 2 outlook will be updated by 0830Z. Day 3 The Day 3 outlook will be updated by 0830Z. Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/94epoints.txt__;!!DZ3fjg!8xC-3PyxuSYo8M_RJ50eNy2LsFClzTMvg1IdF_xXh5IA= O97VbliRdo2172OK0_J4t3TMT2CJYDRO9K8FKqThZ2w9KZg$=20 Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/98epoints.txt__;!!DZ3fjg!8xC-3PyxuSYo8M_RJ50eNy2LsFClzTMvg1IdF_xXh5IA= O97VbliRdo2172OK0_J4t3TMT2CJYDRO9K8FKqThRrjmZug$=20 Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/99epoints.txt__;!!DZ3fjg!8xC-3PyxuSYo8M_RJ50eNy2LsFClzTMvg1IdF_xXh5IA= O97VbliRdo2172OK0_J4t3TMT2CJYDRO9K8FKqThFq9duqk$=20 $$ =3D =3D =3D 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) .