Subj : MESO: Nws Weather Prediction Center College Park Md To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Sat Oct 18 2025 13:05:59 AWUS01 KWNH 181305 FFGMPD MOZ000-ARZ000-OKZ000-KSZ000-181904- Mesoscale Precipitation Discussion 1200 NWS Weather Prediction Center College Park MD 905 AM EDT Sat Oct 18 2025 Areas affected...MO/KS/AR/OK border area Concerning...Heavy rainfall...Flash flooding possible Valid 181304Z - 181904Z Summary...There is growing convective coverage near the MO/KS/AR/OK border region. Hourly amounts to 2" with local amounts to 4" are expected, which could lead to isolated to widely scattered flash flooding. Discussion...WSR-88D radar and SPC mesoanalyses reveal a noticeable decrease in CIN across the area, which is leading to increased shower and thunderstorm coverage near the MO/KS/AR/OK border region. A significant shortwave is approaching the region from the TX Panhandle, which is clearly seen in GOES-19 water vapor imagery. Precipitable water values are 1.42" at Springfield MO, per the 12z sounding. MU CAPE of 500-1500 J/kg lies in the region per SPC mesoanalyses. Effective bulk shear is 40 kts. The flow at 850 hPa in convergent into the region ahead of a frontal boundary. The guidance shows increasing moisture into the region, due to both convective coverage and a slight uptick in low-level inflow into the region. Both the 850 hPa convergence and incoming front are expected to remain foci for convective activity as we move through the late morning into the early afternoon, which should further increase in coverage and intensity with time. Convection could lay down a mesoscale boundary across southern MO and northwest AR with time. Both the 06z HREF and 00z REFS appear to be too far to the east initially with areas receiving heavy rainfall, but the RAP guidance shows boundary layer moisture convergence extending eastward across portions of southern MO, so the expectation is for a convective band to attempt to form with embedded mesocyclones, with each meoscyclone both capable of heavy rainfall on its own and holding up any convective band forward propagation temporarily. This should lead to hourly rain amounts to 2" with local totals to 4" which would be most problematic in urban areas and Ozarks. Isolated to widely scattered occurrences of flash flooding is expected. Recent dryness should keep other areas from seeing significant impacts, so long as the convective development isn't more efficient than forecast. Roth ....Please see https://urldefense.com/v3/__http://www.wpc.ncep.noaa.gov__;!!= DZ3fjg!40hfYk-1H3mqxauxt8LFL7ErVg-dzpIVbsmuIKyRedH_g40xaen4MIOLF1Nof91U35gm= jI6Yxkb353ch7ObsDOa3sIg$ for graphic product... ATTN...WFO...EAX...ICT...LSX...LZK...SGF...TSA... ATTN...RFC...KRF...MSR...ORN...TUA...NWC... LAT...LON 38589292 37719078 36169372 35669512 36309577=20 37949468=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) .