Area Forecast Discussion
Issued by NWS Kansas City/Pleasant Hill, MO
Issued by NWS Kansas City/Pleasant Hill, MO
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869 FXUS63 KEAX 181115 AFDEAX Area Forecast Discussion National Weather Service Kansas City/Pleasant Hill MO 615 AM CDT Tue Aug 18 2026 .KEY MESSAGES... - Severe thunderstorms are possible today and tonight, with the most likely timing from late this evening through the overnight hours. - Near-normal temperatures likely Wednesday into early next week with low precipitation chances, mainly early next week. && .DISCUSSION... Issued at 224 AM CDT Tue Aug 18 2026 A convective system is moving southeast through Nebraska as of 07Z and how this system evolves through sunrise and beyond will play a major role in where/ how convection develops/ evolves this afternoon and through the overnight. Anticipating this system will weaken as it moves southeast and begins to affect the northwestern portions of the forecast area early this morning. Instability is substantially weaker over northwestern and north central Missouri, which should favor a weakening trend as it approaches the area. That said, there is some potential for it persist further southeast and bring some strong wind gusts into northwestern Missouri early this morning. Cloud cover associated with the decaying MCS may limit the potential instability over the norther tier of Missouri and overall, the slight risk has been consolidated more to the southwestern extent of the previous outlook. This evening, the surface pattern will feature an area of low pressure over southern Kansas, with a what looks like a warm front extending east into the southern portions of the forecast area. This will lead to MLCAPE values as high as 2500J/kg across eastern Kansas and western Missouri. As a subtle shortwave trough moves east, increasing flow aloft will support deep-layer shear increasing to over 40 kts. A strong low-level jet will also develop with strong moisture transport northward into the boundary. Convergence along this boundary will get the main convective episode going and will initially support supercells with a large hail and damaging wind threat, though a tornado or two can`t be ruled out as well. Over time, this will evolve into a more linear/bowing segment with damaging winds becoming the main hazard. Overall, the most likely window for severe storms looks like roughly 02Z/9PM through 09Z/4AM. In addition to the severe weather threat, high precipitable water values will support localized heavy rainfall and potential for flash flooding. The area is also under a slight risk for excessive rainfall. Looking over flash flood guidance, values are fairly high 2-3"/hr for areas where the greatest QPF is situated so will not be issuing a flood watch with this forecast. For the remainder of the forecast, temperatures will be closer to normal for this time of year, which is generally in the middle to upper 80s. Ensemble mean 500mb heights and anomalies favor northwesterly flow over the middle of the country with ridging over the western half of the CONUS and troughing over the eastern half. This pattern looks generally dry, and that is generally what the forecast shows. But we`ll need to watch for embedded shortwaves and/or internal PV anomalies generated from upstream convection, that may affect the area. These are not resolvable on this scale, both spatially and temporally, thus the generally dry forecast. && .AVIATION /12Z TAFS THROUGH 12Z WEDNESDAY/... Issued at 616 AM CDT Tue Aug 18 2026 Challenging forecast for eastern KS and western MO this forecast period. Fairly widespread convection is ongoing NW of the area that is tracking SE, but into a less favorable environment for convective maintenance, at least early on. It`s possible (20-40%) that the storms in NE eventually build SE into the terminals later this morning/early this afternoon. Have added a PROB30 group to denote this potential. Later in the period, additional storms seem likely to develop over eastern KS and western MO, affecting all sites between 03Z and 08Z. Have added another PROB30 group to capture this potential. VFR conditions are expected outside of any convective activity. Winds will primarily be light out of the south early in the period. A gust front from the decayed MCS in northern MO may temporarily shift winds to the north this morning. This evening and overnight, winds shift to the east as a boundary sets up south of the area with winds remaining generally light, outside of convection. && .EAX WATCHES/WARNINGS/ADVISORIES... MO...None. KS...None. && $$ DISCUSSION...CDB AVIATION...CDB