114 FXUS63 KEAX 301731 AFDEAX AREA FORECAST DISCUSSION National Weather Service Kansas City/Pleasant Hill MO 1231 PM CDT Fri Jun 30 2023 .Discussion... Issued at 320 AM CDT FRI JUN 30 2023 Key Messages - Shower and thunderstorms are expected to move across far northern MO this morning exiting around midday. Some strong to severe storms are possible. - Dangerous heat continues with highs once again reaching near 100F for many areas south of the MO River. - More storms are possible late Friday into Saturday as cooler conditions enter the area. Detailed Discussion There are two primary concerns overnight. The first being the potential for strong to severe storms Friday morning and the second being the ongoing dangerously hot conditions. A leeward shortwave is working its way across north central KS and southeast NE. A subtle warm front is located just south of US-50 with another subtle boundary near the MO/IA border. The nocturnal LLJ has been gradually intensifying through the night feeding warmer and more moist air across SE NE, NE KS, and NW MO ahead of the storm system. Analysis of the position of the exit region of the LLJ compared to the orientation of the 1000-500mb thickness as well as propagation vectors show the complex moving ENE then wrapping back toward the SE as the system approaches eastern MO. As we have watched the storms progress through the overnight, it seems that the more robust cells are a little further north than anticipated which looks to keep a majority of the activity across southern IA. However, the environment remains fairly unstable with ample moisture, 1000-2000 J/KG of CAPE, and steep midlevel lapse rates. As the MCS progresses and becomes more organized, stronger storms are forming in SE NE. This southward development of storms is expected to continue; therefore, the chance for strong to severe storms across northern MO remains. Areas along and north of the US-36 corridor are the primary focus areas for strong to severe storms; however, storms are expected to extend southward possible reaching the northern sides of the KC metro. High winds, hail, and heavy rainfall remain the primary hazards. Timing of storms has been somewhat difficult as the system builds eastward momentum and discrete cells develop ahead of the MCS. Current expectations are for storms to enter NW MO around 5-7AM and move through the northern MO fairly briskly exiting around midday. Dangerous heat continues regardless of if you experience any rainfall. Temperatures once again climb toward 100F which will not be very difficult since overnight lows look to bottom out in the mid to upper 70s for many, especially south of the MO River. Regardless if the air temperatures tops triple digits, it is likely heat indices will top 100F with several areas south of I-70 potentially seeing heat index values of 105-108F. THerefore, the heat advisory will continue through the day Friday. Cooler air does work its way into the area overnight Friday into Saturday. High temperatures Saturday reset the 80s to low 90s. Scattered showers and thunderstorms are also anticipated as the cooler air moves in which might add a nice bonus to the heat relief. Once again, higher chances for showers and thunderstorms reside north of I-70 with greater chances along and north of the US-36 corridor. Coverage does look to be a little more broad with scattered chances throughout Saturday becoming more widespread as the evening approaches. A surface high moves southward from central Canada quieting conditions Sunday afternoon through the early part of next week. Temperatures looks to steadily climb back toward the mid 90s before another cold front moves through Wednesday into Thursday reverting temperatures back toward the 80s. This slow moving cold front also looks to bring another chance for showers and thunderstorms Wednesday and Thursday. && .Aviation...(For the 18Z TAFS through 18Z Saturday Afternoon) Issued at 1227 PM CDT FRI JUN 30 2023 Shower and thunderstorm activity is expected to develop this evening. For right now, it looks like MCI and STJ will have the highest chance of being impacted. Expect some dry time overnight but shower or thunderstorms will be possible again Saturday morning. && .EAX WATCHES/WARNINGS/ADVISORIES... KS...Heat Advisory until 7 PM CDT this evening for KSZ025-057-060- 103>105. MO...Heat Advisory until 7 PM CDT this evening for MOZ028>033-037>040- 043>046-053-054. && $$ Discussion...Pesel Aviation...HB