Subj : MESO: Nws Weather Prediction Center College Park Md To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Sat Aug 05 2023 10:02:51 AWUS01 KWNH 051002 FFGMPD ILZ000-051500- Mesoscale Precipitation Discussion 0869 NWS Weather Prediction Center College Park MD 602 AM EDT Sat Aug 05 2023 Areas affected...Central illinois Concerning...Heavy rainfall...Flash flooding likely Valid 050959Z - 051500Z SUMMARY...Heavy rain and flash flooding from a potent low=20 continues drifting east over central Illinois rest of this morning. Rainfall rates of 2 to 3 inches per hour and up to 5 inches in two hours should overcome the dry antecedent conditions, so flash flooding is considered likely. DISCUSSION...Regional NEXRAD denotes a well defined MCV north of a surface low over western IL is slowly drifting east. Maintenance of a convergent swath east and around the north side of the low will continue across central IL as southerly low level inflow brings unstable air from southern IL on top of high moisture under the MCV and south through southwestern IL with PW of 2 to 2.2". The deeper moisture intersection near the surface low and northward should continue to have ample narrow skinny CAPE for strong updrafts and moisture flux for 2-3"/hr rates through the rest of the morning. Slow, nearly due eastward progression of the MCV/surface wave should keep orientation of some cells to align favorably for longer duration and support a swath of highest two hour rainfall totals of 3 to 5" possible. Central IL has been generally dry over the past several days, with FFG generally around 3"/3hr. However, given the slow motion and highly efficient rainfall of longer than an hour duration, flash flooding is considered likely through 15Z. One wildcard is the presence of the stationary front just to the east. Whether the southerly flow can maintain enough instability to allow further heavy rain is a bit of a question. Jackson ....Please see https://urldefense.com/v3/__http://www.wpc.ncep.noaa.gov__;!!= DZ3fjg!5rjmp9VSfY8wrISH0ph3T2LqWDkyp4Gio9dl-pZUVbQxM2sXA4QmtAgShhGsTCYGXwdR= 0bS6f2GiuqWdiHq7xBijKjk$ for graphic product... ATTN...WFO...DVN...ILX...LOT...LSX... ATTN...RFC...NCRFC...NWC... LAT...LON 41228973 41128902 40728848 39728868 39498943=20 39629034 40269062 40749096 41059063 41169021=20 =20=20=20=20=20=20=20=20=20=20=20=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) .