Subj : MESO: Nws Weather Prediction Center College Park Md To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Thu Jun 26 2025 07:47:55 AWUS01 KWNH 260747 FFGMPD IAZ000-NEZ000-SDZ000-261346- Mesoscale Precipitation Discussion 0518 NWS Weather Prediction Center College Park MD 347 AM EDT Thu Jun 26 2025 Areas affected...much of Nebraska, western Iowa Concerning...Heavy rainfall...Flash flooding likely Valid 260746Z - 261346Z Summary...Flash flood potential continues - especially near Grand Island, NE where 5-10 inches of rainfall has occurred over the past 12 hours. Discussion...Extensive flash flood impacts have occurred near Grand Island, NE earlier, where a couple of convective bands began to train over the region and produce 3-6 inches of rainfall over the past 6 hours. Since that time, upscale growth and slight weakening of convection across south-central Nebraska has enabled the heaviest rain to propagate just east of the Grand Island region. Unfortunately, an upstream mid-level impulse and convergence on the nose of 40-kt 850mb flow over Kansas to produce renewed convection across west-central Nebraska. These storms will allow for continued rainfall and perhaps another 1 inch of rain on top of prior significant rainfall, potentially exacerbating impacts near the Grand Island area. This additional rainfall risk will persist for at least another 3 hours or so (through 1030Z/5:30am CDT) until the upstream mid-level impulse passes the region. Additional rainfall will persist east of Grand Island through Columbus, Omaha Metro, and portions of western Iowa through 13Z/8a CDT. Rain rates should remain relatively low with this activity due to modest instability and appreciable (30-kt) movement, although prior rainfall (as much as 3-5 inches along this axis) have lowered FFG thresholds and made ground conditions sensitive/conducive for excessive runoff. Another 1-2 inches of rainfall along this axis could contribute to isolated/continued flash flooding this morning. Cook ....Please see https://urldefense.com/v3/__http://www.wpc.ncep.noaa.gov__;!!= DZ3fjg!660RDQVwhQ_JLiGJwL0-ycC7Ntvk-y0Ae1_dO8cUkgI72PGxXmyuryxESTa5kOtl_LaH= MAyEbw4WCLQwH0U7emlxWsI$ for graphic product... ATTN...WFO...DMX...FSD...GID...GLD...LBF...OAX... ATTN...RFC...KRF...MSR...NWC... LAT...LON 43109403 42439339 41599368 40889554 40269810=20 40150037 40600098 41470061 42119875 42659595=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 3.20-Linux * Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105) .