Subj : MESO: Nws Weather Prediction Center College Park Md To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Tue Jul 08 2025 00:06:43 AWUS01 KWNH 080006 FFGMPD IAZ000-NEZ000-SDZ000-080600- Mesoscale Precipitation Discussion 0617 NWS Weather Prediction Center College Park MD 806 PM EDT Mon Jul 07 2025 Areas affected...Eastern NEB...Western IA...Far Southeast SD... Concerning...Heavy rainfall...Flash flooding possible Valid 080005Z - 080600Z SUMMARY...Merging clusters of severe weather and increasing mositure flux pose short-term intense bursts of heavy rainfall and localized totals of 2-3.5" and possible flash flooding. DISCUSSION...Regional RADAR mosaic and GOES-E Visible imagery show a large cluster of thunderstorms at the base of northern stream shortwave trough crossing the Red River of the North where surface warm front has lifted across the Missouri River Valley slowly today. Southerly low level winds of 850mb have been steadily increasing moisture return with Tds in the upper 60s and lower 70s. While mid-level moisture is enahnced across the 700-500mb layer at this intersection of the northern stream trof and the returning moisture. As such, total Pwats are increasing to 1.75" and strong convective clusters with severe winds/hail are going to increase in rainfall efficiency over the next few hours. However, in the short-term some cells that have developed on the southerly WAA in northeast NEB continue to lift north and will start to merge with the southeastward cluster. This merger will rapidly enhanced rainfall rates to over 2"/hr and may slow the fairly progressive southeastward push of the overall system.=20 Isolated spots of 3"/hr while uncommon, may result and may quickly overwhelm any soil condition; dry/wet or normal. However, deep layer steering and cold pool generation will quickly overcome that initial intersection and track/repeat southeastward likely limiting overall totals thereafter, especially further north and east within the overall complex. Though in the wake of the cluster, low level jet flow will remain out of the south an increase to 20-25kts and with some further veering may allow for further isentropic development along the flanking line. As such, upwind redevelopment will have the potential for training allowing for spots of 2-3.5" to occur, likely across northeat NEB just east of the Sand Hills over areas of FFG values of 1.5-2"/hr and 2-2.5"/3hrs. As such, incidents of flash flooding may be possible along the flanking line through the early overnight period toward 06z.=20 Gallina ....Please see https://urldefense.com/v3/__http://www.wpc.ncep.noaa.gov__;!!= DZ3fjg!7DaC-9TeZrNxh5SYyWEbYO7L_7VfLJnKplVtaTbO7d7ymnYRmtTOUX7NjBT2X9liQ4P0= F_QMYTuBMAqF05MGFElxfRc$ for graphic product... ATTN...WFO...DMX...FSD...GID...OAX... ATTN...RFC...KRF...MSR...NWC... LAT...LON 43519732 43299628 42679539 41899478 41229523=20 40909629 40939748 41549807 42519825 43049815=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) .