Subj : MESO: Nws Weather Prediction Center College Park Md To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Mon Aug 04 2025 19:30:16 AWUS01 KWNH 041930 FFGMPD KYZ000-INZ000-ILZ000-MOZ000-050100- Mesoscale Precipitation Discussion 0866 NWS Weather Prediction Center College Park MD 328 PM EDT Mon Aug 04 2025 Areas affected...Lower OH Valley Concerning...Heavy rainfall...Flash flooding possible Valid 041928Z - 050100Z SUMMARY...Slow-moving showers and thunderstorms with high rainfall rates will be expected through early this evening. A localized threat of flash flooding will exist. DISCUSSION...The latest GOES-E WV suite shows an upper-level trough and closed mid-level low center drifting slowly off to the east into the Lower OH Valley. This energy is interacting with a pool of moderate instability which is characterized by MLCAPE values of 1000 to 1500+ J/kg, and the latest radar imagery shows clusters of slow-moving showers and thunderstorms expanding in coverage across especially portions of central and southern IL along with southwest IN. Multiple surface boundaries/troughs are in place as well which coupled with at least modest DPVA associated with the upper-level trough should favor some sustainable forcing. This coupled with the instability should yield some additional expansion of showers and thunderstorms over the next few hours. The PWs are relatively high with values of 1.5 to 1.75 inches in place, and with the available instability, some rainfall rates of 1 to 2 inches/hour will be likely with the stronger storms that evolve going through the early evening hours. Slow cell-motions are in place given the overall steering flow, with some of the convection already locally anchored near some of these more subtle surface boundaries. These slow cell-motions and fairly high rainfall rates may support some rainfall totals of 2 to 4+ inches through early this evening. A localized threat of flash flooding will exist as a result, which may include some isolated urban flooding impacts as well. Orrison ....Please see https://urldefense.com/v3/__http://www.wpc.ncep.noaa.gov__;!!= DZ3fjg!4AeSLUc27tirh21uxTRarf_UFZP2mdhpy_vFrAsWc3_a1WJHes0z6k3qnWIg2sj2UmTv= GCgW39JthFY4aQ-tVzHm5lo$ for graphic product... ATTN...WFO...ILX...IND...LMK...LSX...PAH... ATTN...RFC...MSR...ORN...TIR...NWC... LAT...LON 39578757 39228650 38488555 37838574 37728658=20 37558764 37278855 37428948 38129004 38898991=20 39458904=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 3.28-Linux * Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105) .