Subj : HVYRAIN: Excessive Rainfall Discussion To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Tue Apr 18 2023 00:06:40 FOUS30 KWBC 180006 QPFERD Excessive Rainfall Discussion NWS Weather Prediction Center College Park MD 805 PM EDT Mon Apr 17 2023 Day 1 Valid 01Z Tue Apr 18 2023 - 12Z Tue Apr 18 2023 The probability of rainfall exceeding flash flood guidance is less than 5 percent. Hurley Day 2 Valid 12Z Tue Apr 18 2023 - 12Z Wed Apr 19 2023 ....20Z Update... The probability of rainfall exceeding flash flood guidance is less than 5 percent. Wegman Day 3 Valid 12Z Wed Apr 19 2023 - 12Z Thu Apr 20 2023 ....THERE IS A MARGINAL RISK FOR EXCESSIVE RAINFALL FROM THE CENTRAL PLAINS TO THE UPPER MISSISSIPPI VALLEY... ....20Z Update... No big changes were made to the Marginal Risk area from northeastern KS through WI. While the guidance is honing in on strong and some severe thunderstorms traversing the area Wednesday afternoon, there is still some uncertainty as to where the greatest chances of training thunderstorms will be. With as high as 2,000 J/kg of CAPE in KS, and about an inch of PWAT, there is some potential that with better agreement a Slight Risk may be needed with future updates for a portion of the Marginal Risk area. While KS will have the most instability, antecedent conditions are most favorable for flash flooding in WI due to recent snowmelt and added snowmelt from the current winter storm in the western half of the state. Wegman ....Previous Discussion... Return moisture from the Gulf of Mexico will be drawn northward through the central U.S. while a couple of low pressure waves over the Central Plains interact with a slow-moving frontal boundary. Locally heavy rain will be possible, especially from Kansas/Missouri northeastward to Wisconsin/Michigan where areal average QPF will range 1 to 2 inches. Much of this part of the country has lowered FFG due to recent/ongoing snowmelt and rain. There will be an elevated threat for some of the convection to produce locally heavy rainfall over these nearly saturated areas. A Marginal Risk is in effect from eastern Kansas to Wisconsin. Campbell Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/94epoints.txt__;!!DZ3fjg!_YpR1unXu47j2ynToMXJ31AM6-cBypSLcnGtXk9mzIeR= 9exn2BwA7klga1v4kmsU4beJX-5mYFy1G9XPnE8KxsoOlDY$=20 Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/98epoints.txt__;!!DZ3fjg!_YpR1unXu47j2ynToMXJ31AM6-cBypSLcnGtXk9mzIeR= 9exn2BwA7klga1v4kmsU4beJX-5mYFy1G9XPnE8KFekqx94$=20 Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/99epoints.txt__;!!DZ3fjg!_YpR1unXu47j2ynToMXJ31AM6-cBypSLcnGtXk9mzIeR= 9exn2BwA7klga1v4kmsU4beJX-5mYFy1G9XPnE8Kb5Qsukc$=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) .