Subj : HVYRAIN: Excessive Rainfall Discussion To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Mon Aug 28 2023 08:30:04 FOUS30 KWBC 280829 QPFERD Excessive Rainfall Discussion NWS Weather Prediction Center College Park MD 429 AM EDT Mon Aug 28 2023 Day 1 Valid 12Z Mon Aug 28 2023 - 12Z Tue Aug 29 2023 ....A SLIGHT RISK OF EXCESSIVE RAINFALL IS IN EFFECT FOR PORTIONS OF THE SOUTHEAST AND SOUTHERN MID-ATLANTIC... ....Southeast U.S into Southern Mid-Atlantic... Stalled frontal boundary across the southeast U.S will again be the focal point for a corridor of heavy rainfall during peak diurnal convection on Monday afternoon and evening. The corridor of higher theta-e located along the boundary and weak steering flow will provide an axis in which rainfall rates exceed 2 inches per hour from the most intense convection. 28/00Z HREF CAM consensus is for two general areas of precip maxima; the southern Appalachians to Upland portions of South Carolina down through northern Georgia, and southeast Virginia and northeast North Carolina. Saw little need to make changes except to trim the far southern extent out of the area. It does not preclude isolate run-off problems in urban areas or in areas with poor drainage...but the overall concern for excessive rainfall is near the front farther north. ....Florida Peninsula... Kept the Marginal Risk area over parts of the west and southwest Florida peninsula coast for continued consensus from the latest guidance about leading/outer bands of Idalia late Monday night...which is generally limited to this more sensitive urban corridor from Tampa Bay through Naples. Diurnally forced activity across the rest of the southern peninsula is expected as tropical moisture streams into the area ahead of Idalia. As mentioned previously...any excessive rain concern elsewhere across the Florida peninsula should be isolated given the recent generally dry weather and high flash flood guidance. ....Colorado through West Texas.... Late day and evening convection is expected once again from Colorado into West Texas on Monday downstream of a strong ridge axis. Flow aloft increases as it veers a bit from northwesterly to north-northwesterly as rdge axis approaches. This will help focus activity closer to the eastern slopes of the southern Rockies than recently. In general...a localized excessive rainfall event is anticipated...aA localized Slight Risk may be warranted should a focus area on Monday repeat over areas of heavy rain through tonight. In general...a localized excessive rain risk is anticipated. Bann 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!-tVWaPIyBlfrUuQzKYZYSVrXFYmCBSFD_VbGRNcwR1Dv= r2aAmqS-jARd8T6rtEAGpOMgGmKWbGsnU0P8K9m7QaPIl74$=20 Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/98epoints.txt__;!!DZ3fjg!-tVWaPIyBlfrUuQzKYZYSVrXFYmCBSFD_VbGRNcwR1Dv= r2aAmqS-jARd8T6rtEAGpOMgGmKWbGsnU0P8K9m7Eay1978$=20 Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/99epoints.txt__;!!DZ3fjg!-tVWaPIyBlfrUuQzKYZYSVrXFYmCBSFD_VbGRNcwR1Dv= r2aAmqS-jARd8T6rtEAGpOMgGmKWbGsnU0P8K9m7ykqEOJ4$=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) .