Subj : MESO: Nws Weather Prediction Center College Park Md To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Mon Jun 30 2025 01:42:48 AWUS01 KWNH 300142 FFGMPD ARZ000-OKZ000-KSZ000-300700- Mesoscale Precipitation Discussion 0553 NWS Weather Prediction Center College Park MD 942 PM EDT Sun Jun 29 2025 Areas affected...southeast Kansas, northeast Oklahoma Concerning...Heavy rainfall...Flash flooding possible Valid 300141Z - 300700Z Summary...Showers and thunderstorms will expand along several outflow boundaries tonight. Rainfall rates in new convection may briefly pulse up above 3"/hr, leading to 1-2" of rain in less than 1 hour. Flash flooding is possible. Discussion...The regional radar mosaic this evening shows clusters of thunderstorms dropping southward across parts of AR, OK, and KS along residual outflow boundaries from earlier convection. Radar estimated rainfall rates within the most intense cores have been above 2"/hr according to KVNX, which has resulted in MRMS measured rainfall of more than 3 inches in the past 6-hrs in a few locations, including a reported 3.9 inches near Piedmont, KS. These outflows will continue to drop steadily southward through the next several hours, serving as a focus for additional convective development. As the boundaries drop south, they will encounter more favorable thermodynamics reflected by the SPC RAP analysis indicating a pool of 2500-3500 J/kg of MLCAPE aligned with a ribbon of PWs approaching 2 inches. This will continue to support intense rainfall rates of more than 2"/hr, and the HRRR 15-min rainfall accumulation product suggests rates will briefly exceed 3"/hr (0.75 to 1 inch in 15 minutes). Additionally, as these storms sag south and redevelop along the convergent outflow boundaries, the LLJ, currently analyzed via local VWPs to be from the SW at 20 kts, will provide additional ascent through isentropic upglide while concurrently resupplying the impressive thermodynamics into the clusters of storms. While the CAMs are exceptionally different with the evolution the next few hours, the recent HRRR appears to be catching on to the current activity, with some support from the ARW/ARW2 as well. Despite the lack of agreement, which is negatively impacting the HREF exceedance probabilities, the current radar combined with the expected continuation of the favorable thermodynamics suggests convection will persist, and may pulse up at times through the next few hours. Where this occurs, total rainfall could again be 1-2" in less than an hour, with local maxima above 3" possible. This rain will occur atop soils that are saturated above the 90th percentile according to NASA SPoRT from 7-day rainfall that has been more than 200% of normal, highest in northeast OK. Any heavy rain falling atop these soils, especially if any training can occur along the boundary as it sags southward, could cause instances of flash flooding. Weiss ....Please see https://urldefense.com/v3/__http://www.wpc.ncep.noaa.gov__;!!= DZ3fjg!5ry-0Q7fP_V0EQdGocVrPcaNGadbPKLFALlvxxBrHbcEJrFNC4VmT5qzSG1IPAFDpChz= bsV_QfYSy6YLpAjvKLx9AZk$ for graphic product... ATTN...WFO...ICT...OUN...TSA... ATTN...RFC...TUA...NWC... LAT...LON 37999698 37859578 37169522 36619478 36199445=20 35569430 35199456 35129520 35299608 35679697=20 36149750 36609785 37319784=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) .