Subj : MESO: Nws Weather Prediction Center College Park Md To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Thu Aug 03 2023 07:11:01 AWUS01 KWNH 030710 FFGMPD TNZ000-KYZ000-ILZ000-MOZ000-031030- Mesoscale Precipitation Discussion 0845 NWS Weather Prediction Center College Park MD 310 AM EDT Thu Aug 03 2023 Areas affected...central/southeastern MO into the Lower OH Valley Concerning...Heavy rainfall...Flash flooding likely Valid 030708Z - 031030Z Summary...Training of thunderstorms is likely to continue producing areas of flash flooding across portions of central/southeastern MO into the Lower OH Valley through 10Z. Rainfall rates of 2 to 3 in/hr are expected, although rates locally in excess of 3 in/hr cannot be ruled out. Given overlap with recent heavy rainfall, some areas of flash flooding could be serious/significant. Discussion...Regional radar imagery at 0630Z showed an axis of training thunderstorms over east-central MO, from just north of Jefferson City to near Saint Clair on I-44. This axis has recently organized over the past hour, about 25-50 miles northeast of an estimated 3-6 inches of rain which fell since 00Z over parts of Morgan, Moniteau and Cole counties. While the heavy rain axis to the south has recently ended, the potential for training will remain through the morning. Rainfall rates have averaged 1-2 in/hr, but with much of these totals falling in about 30 minutes and locally above 2 in/hr since 00Z. WSW 850 mb winds of 20-35 kt were observed on KLSX, KSGF and KPAH VAD wind plots, with overrunning of a quasi-stationary front in southwestern MO helping to support the elevated axis of convection. Mean steering flow oriented parallel to the axis of elevated convergence will continue over the next several hours per recent RAP forecasts. However, as a subtle 850 mb low in northern MO tracks toward the east through 12Z, some strengthening and veering of low level flow is expected which should have the effect of translating the axis of heaviest rain toward the south, perhaps starting around 10Z. Downstream, an MCV over southern IL was tied to a forward propagating line of thunderstorms stretching from southern IL into southeastern MO. As the MCV continues to track toward the ESE, areas of training heavy rain are likely to maintain in its wake from portions of southeastern MO across the OH River into western KY and northwestern TN, supporting an additional flash flood threat across these downstream areas. However, the greatest concern for significant/serious flash flooding will be in central to eastern MO where heavy rain over the past 48 hours has supported increased water levels on area rivers and streams along with producing saturated soils. Areas of flooding are already ongoing in these locations and the addition of another 2-4 hours of training with rainfall rates possibly above 2 in/hr will make for a dangerous, life-threatening situation on the ground. Otto ....Please see https://urldefense.com/v3/__http://www.wpc.ncep.noaa.gov__;!!= DZ3fjg!-25HsSSjJWAvh-Z5yGuvFJKsehth3NXLO_5Z-JYD5hjfoDCIeo8y66mWmXm_UZkgRSTk= BhOIc202ZhrCRpF495z__DA$ for graphic product... ATTN...WFO...EAX...LSX...MEG...OHX...PAH...SGF... ATTN...RFC...LMRFC...MBRFC...NCRFC...OHRFC...NWC... LAT...LON 39079258 38659068 38008933 37118812 36348800=20 36068861 36228932 36739026 37209105 38089268=20 38579324=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) .