####018005591#### FXUS63 KEAX 041220 AFDEAX Area Forecast Discussion National Weather Service Kansas City/Pleasant Hill MO 720 AM CDT Sat May 4 2024 .KEY MESSAGES... - Scattered showers and thunderstorms will move through the area this morning. A few strong storms may be possible. - Widespread showers and thunderstorms are likely Monday night into early Tuesday morning. Large hail, damaging wind gusts, a few tornadoes, and locally heavy rain will all be possible. - The active weather pattern continues into Tuesday and Wednesday, with strong to severe storms possible. && .DISCUSSION... Issued at 246 AM CDT Sat May 4 2024 A line of thunderstorms is ongoing from southwestern Iowa, through extreme NW Missouri, and into eastern Kansas as a shortwave trough and associated cold front are working their way from the Central Plains into the Midwest. As of 3 am, the most robust storms are located just east northeast of Manhattan KS (reports of dime sized hail and wind gusts up to 45 mph) with these moving to the northeast. SPC mesoanalysis shows a corridor of 250 to 500 J/kg of surface based CAPE over far eastern KS into far western/NW MO, with up to 1000 J/kg of most unstable CAPE. Up to 35 knots of 0 to 6 km wind shear is in place over NE KS and NW MO, with weaker shear elsewhere. This suggests that the most likely location for any stronger storms would be across NE KS and NW MO. Total rainfall amounts should range from 0.5" to 0.75" in this area. Storms should weaken east they continue eastward later this morning, and convection allowing models keep the KC metro mostly dry this morning. New development of showers and storms is possible ahead of the cold front this afternoon from Kirksville southward toward Columbia, with these exiting the county warning area by late afternoon. Cloud cover will likely linger into the mid to late afternoon hours, with winds turning northwesterly and eventually northerly behind the cold front. The timing of the front will create a relatively large temperature gradient for high temperatures today, with highs only forecast to reach the lower 60s over NW Missouri but highs as warm as the mid to even upper 70s toward mid Missouri where the front will likely not arrive until mid afternoon. By tomorrow afternoon, a 548 dam closed low at 500 mb moves into the Grand Basin region of Nevada and Utah, with associated troughing moving into the Desert Southwest. Meanwhile, a more subtle shortwave trough develops over the ArkLaTex region and sends the stalled cold front over the Arkansas Ozarks northward. This could generate some showers and thunderstorms on Sunday afternoon, especially for areas south of Interstate 70, although the better chances should stay south of our region toward the Interstate 44 corridor. As we head into Monday, a potent mid/upper trough comes across the Southern Rockies, undergoing lee cyclogenesis and progressively becoming more negatively tilted as it ejects across the Central and Northern Plains. Models have come into better agreement, suggesting a deep surface low developing over the Northern High Plains, with a warm front extending east/west over NE/IA and a dryline extending southward through west- central KS and Oklahoma by Monday afternoon. With good moisture return, moderate to high instability, and excellent deep layer shear thanks to a 50 to 70 knot mid level jet, supercells with highly impactful severe weather of all types appears likely Monday afternoon and evening across portions of southern NE/central KS/central OK. It seems likely that these storms will grow upscale into a severe squall line/MCS as they progress eastward toward our region on Monday evening. Prime time for our region appears to be late evening into the overnight/early morning hours of Tuesday. If any storms do manage to develop out ahead of the expected squall line, all severe hazards would be very much in play. However, if it is a squall line, damaging wind gusts and potentially some embedded QLCS mesovortex tornadoes would likely be the main concern. Additionally, widespread moderate rain is likely, with rainfall totals on the order of around 1 inch with locally higher amounts possible, potentially yielding more flash flooding and river flooding. The active pattern continues on Tuesday and Wednesday as the closed mid level low is progged to remain over the Northern Plains with southwesterly flow aloft over our region. With moderate instability and strong deep layer wind shear hanging around Tuesday and Wednesday afternoon/evening, strong to severe thunderstorms will remain possible. As such, SPC has highlighted portions of our county warning area within a 15% risk for severe storms for both Tuesday and Wednesday. && .AVIATION /12Z TAFS THROUGH 12Z SUNDAY/... Issued at 719 AM CDT Sat May 4 2024 MVFR ceilings are expected to remain through the morning and may linger into the afternoon as well. There are some showers in western Missouri ahead of a cold front as of 12Z, but they are expected to move east of the TAF sites after 15Z. A surface cold front is forecasted to move through today. Ceilings are expected to begin lifting and winds will shift to the north behind the front. && .EAX WATCHES/WARNINGS/ADVISORIES... MO...None. KS...None. && $$ DISCUSSION...Williams AVIATION...Collier