FXUS63 KEAX 241405 AFDEAX Area Forecast Discussion National Weather Service Kansas City/Pleasant Hill MO 905 AM CDT Wed Apr 24 2024 .KEY MESSAGES... - Heads Up: Multiple rounds of thunderstorms beginning Thursday, continuing through Sunday. - Severe thunderstorm chances Friday, Saturday, and Sunday. - Heavy rainfall and the potential for flooding with Saturday Evening into Sunday system. && .DISCUSSION... Issued at 239 AM CDT Wed Apr 24 2024 06Z surface analysis reveals the surface ridge continues to develop across the Northern Plains early this morning. This trend will continue as mid-level ridging continues to evolve across the Rockies through today. What does that mean for us? Well, today is the last quiet, nice day, before we enter an active period marked by thunderstorms and rainfall Thursday through Sunday. With light north and finally east-southeast winds today, temperatures will remain seasonable, in the upper 60s to lower 70s. Tonight, with the mid-level ridge shifting east, influenced by the eastward dig of an H500 trough along the West Coast, broadscale forcing for ascent will develop across the Southern Plains and spreading northward through Thursday morning. Tapped into decent Gulf Moisture, rain and showers are expected to develop and spread northward across the region through Thursday morning. Forecast soundings suggest some skinny elevated instability could develop through the mid to late morning, resulting in rumbles of thunder. Through Thursday, as the H500 trough pivots over the Four Corners, anticipate ample recovery across the western High Plains of KS/TXPH/OKPH. With Mid-60s dew points developing from central Kansas into Oklahoma, instability will surge through the afternoon, with an axis of 1500 to 2500 J/Kg of SBCAPE. Mid-range guidance has been in decent agreement with the surface low center lifting out of Colorado into northwestern Kansas through the late afternoon. With a decent dryline positioned from near Goodland KS and South toward Guymon OK, expect convection to develop from the triple point in northwestern Kansas and southward as the cold front advances into western Kansas through the late afternoon and evening. For more details check out the latest SWODY2 from SPC and discussions from the KS, TX, and OK WFOs. For our area, warm sector convection will likely be ongoing through the day across far eastern Kansas and western Missouri, with activity spreading east through the evening and overnight into Friday. A few strong storms may exist during this period, but no widespread severe weather for our area is expected at this time. Friday, as mentioned yesterday, lingering showers/convective activity through the morning would have some limited influence on recovery through midday to the afternoon. The Aforementioned mid- level short wave is expected to lift east-northeast across central Nebraska by midday, maintaining a negative tilt, with the surface low center nearby. Most guidance has ample recovery through the early afternoon, with daytime heating and southerly flow combining for a ribbon of 2000 J/Kg SBCAPE extending from eastern Oklahoma across eastern Kansas into northwestern MO. The focus for severe convective development will be along this axis, but closer to the surface low in southeast Nebraska, northeastern Kansas, and northwestern Missouri where the better dynamics will be. Primarily, latest solutions from mid-range guidance suggests the cold front will overtake the dryline late in the afternoon, with convection firing from southwestern Iowa into northwestern Missouri and south along the boundary as it advances eastward. There is one big issue of note, and I made note of it yesterday. With such an aggressive negative tilt to the trough, southwesterly flow through the lower levels will more than likely result in a decent EML, and forecast soundings confirm this. Now, the front will provide some assist in breaking the capping inversion, but convection may be delayed until later in the afternoon to the early evening because of this. The influence of the EML will probably be felt the further south down the front one travels. The effects are less of an issue in far northeastern Kansas and northwestern Missouri, where initial convection is most likely. All modes of severe weather will be possible given deep layer shear supporting organization. Shear orientation also suggests initial convection to be single cell, with a brief period of backing surface winds in northwest Missouri a concern. Large hail, damaging wind gusts, and a tornado or two are possible with the strongest updrafts Friday afternoon and evening. Convection will steadily exit east overnight through Saturday morning. Saturday, there will be a lull in activity through the morning to midday. Through sunrise, out west, another churning H500 trough crossing the Rockies will emerge on the western High Plains through the day. Ahead of this system, ample return flow from the Gulf will pool across the Plains, with broadscale ascent through the warm sector driving scattered convection through the day from Oklahoma and Arkansas and north. As the surface low lifts east into western Kansas, once again, organized convection will develop along the intersection of the cold front and the dryline, as well as along the warm front across central Kansas through the afternoon and evening. The big concern I have for our area late Saturday into early Sunday will be excessive and continuous moderate to heavy rainfall. With pwats pushing 1.50 to 2.00 inches and the warm front extended from eastern Kansas to northeastern Missouri, training thunderstorms are going to be a big concern overnight. The track of greatest rainfall still looks to be across northern into northeastern Missouri, but thunderstorms will result in locally heavy rainfall and the increased risk of rises on area streams and rivers and flash flooding. Even with the moderate drought for much of the area, the flooding concern exists. Additionally, a few severe storms remain possible, with hail and wind the primary concerns at this time. We'll need to watch any storms that anchor to the warm front given the enhancement of shear brought on by the boundary. Thunderstorms will continue through Sunday across the area, with rainfall amounts from Saturday night to Sunday morning totaling around 2 to 3 inches in many locations, with locally higher amounts possible. Long range guidance continues to suggest modest recovery of the airmass through midday ahead of the northeast churn of the upper short wave over Iowa. In response, a modest instability axis will develop through central Missouri, with convective development expected along the trailing cold front through the afternoon. This will bring us our last window of potential strong to severe convection for the weekend, with focus from central into eastern Missouri. Hail and wind will be the primary concerns, but again, farther north, nearer the more favorable shear environment, a tornado or two cannot be ruled out. Precipitation should end to the east Sunday night. By the end of the weekend, the overall rainfall total from Thursday to Sunday could be upwards of 4 to 6 inches of rain. && .AVIATION /12Z TAFS THROUGH 12Z THURSDAY/... Issued at 904 AM CDT Wed Apr 24 2024 VFR conditions are expected for the duration of the forecast period. Winds remain light generally from the east. && .EAX WATCHES/WARNINGS/ADVISORIES... MO...None. KS...None. && $$ DISCUSSION...Kurtz AVIATION...Pesel