Subj : MESO: Nws Weather Prediction Center College Park Md To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Mon Jun 30 2025 07:01:22 AWUS01 KWNH 300701 FFGMPD KSZ000-NEZ000-301300- Mesoscale Precipitation Discussion 0555 NWS Weather Prediction Center College Park MD 300 AM EDT Mon Jun 30 2025 Areas affected...portions of central Kansas into central Nebraska Concerning...Heavy rainfall...Flash flooding possible Valid 300700Z - 301300Z Summary...A couple of thunderstorm complexes are expected to merge across the discussion area though 12Z this morning. Multiple cell mergers and localized training should enable development of areas of 1-2 inch/hr rain rates and at least isolated instances of flash flooding. Discussion...A complicated convective pattern is evolving across the central Plains currently. A fairly progressive MCS is leveraging modest steering flow aloft while forward propagating southeastward near LXN/Lexington, NE currently. The orientation of the convection and its speed has generally limited rain rates to around 1 inch/hr on an isolated basis, resulting in a very limited flash flood threat in the short term. Farther south, a mature MCS has evolved across southern Kansas/northern Oklahoma. This complex is leveraging both steep lapse rates aloft (around 7.5C/km) and convergence on the nose of a 30kt southwesterly low-level jet centered over northwestern Oklahoma and southwestern Kansas. The storms within this complex have substantially weaker mid/upper steering flow and are largely elevated atop an expanding cold pool. Slow movement has enabled several areas of 1-2 inch/hr rain rates to materialize, which has fostered isolated flash flood potential especially near Wichita where 2 inch/hr FFG thresholds were noted. Over the next 6 hours, the meso-to-synoptic setup favors the eventual merging of the southern Nebraska and southern Kansas MCSs along with intermediate convective development across western/central Kansas amid strong low-level convergence and 2500 J/kg MLCAPE. The increase in convective coverage and relatively weak steering flow aloft suggest that areas of 1.5-2.5 inch/hr rain rates will become more common with time. These rates will exceed FFG thresholds at times - especially across southern NE and northern Kansas where 1.5-2 inch/hr thresholds were prevalent.=20 FFGs are a bit higher with southern extent into Kansas, potentially pointing to a somewhat lesser flash flood threat in those areas. Cook ....Please see https://urldefense.com/v3/__http://www.wpc.ncep.noaa.gov__;!!= DZ3fjg!6JQHJw6bFSfE1RGDj0ImMPJ9b_lyFd0k-sn84KNNkWdKaH90doxwtTnplhRUELr9TzOi= MJgXQ5r8roMwQjvVRbVi3lc$ for graphic product... ATTN...WFO...DDC...GID...GLD...ICT...LBF...OAX...TOP... ATTN...RFC...KRF...TUA...NWC... LAT...LON 41619840 40389698 38819640 37949679 37499729=20 37459882 37990035 39040170 39890137 41260022=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) .