FXUS63 KEAX 051718 AFDEAX Area Forecast Discussion National Weather Service Kansas City/Pleasant Hill MO 1118 AM CST Tue Mar 5 2024 .KEY MESSAGES... - Cooler today, yet temperatures continue above normal. - Precipitation chances return later this week with showers and thunderstorms possible late Wednesday through Friday. && .DISCUSSION... Issued at 303 AM CST Tue Mar 5 2024 Some residual high based showers are very slowly working their way out of the region as the upper level cold front moves into Central MO. Cooler air which flowed in earlier has dropped temperatures 30- 35 degrees lower than Monday afternoon highs. Surface high pressure is building in behind the front keeping skies quiet for Tuesday and much of Wednesday. The northern midlatitude jet stream remains north of the region keeping cold temperatures at bay; however, northwesterly low level flow puts a cap on high temperatures limiting them to the upper 50s and low 60s. The upper level pattern becomes more zonal as west to east flow locks temperatures for the next few days into a 60s/40s split of highs and lows respectively. An upper level shortwave across the northern CONUS spawns a leeward trough in the Upper Midwest which turns low level flow advecting warmer air into the area midweek while simultaneously pushing more moisture into the region. At the same time, a deepening trough moves on shore across southern CA buckling the subtropical jet positioning its exit region across the southern Rockies/SW Plains aimed at the central CONUS. This fosters the development of a lee trough across SW KS which quickly taps into the warm air and moisture advection bringing chances for showers and thunderstorms across the area starting late Wednesday and continuing through Friday. The regional scale meteorological setup of the late week system holds many parallels to what was seen yesterday/overnight with the key difference being a further south and west development bringing better chances for more widespread rainfall than Monday's system. Instability remains rather lacking at this time lowering the potential for severe weather potential. PWAT values reside around an inch and with notable thermal and kinematic boundaries creating ample opportunities for enhanced lift. This presents the potential for heavy downpours within some of these storms. Antecedent dry conditions keep concerns for flash flooding at bay; however, heavy downpours on long dry surfaces can create some pooling/ponding on the ground in conjunction with runoff. Colder air plunges back into the region for the upcoming weekend as flow across all vertical planes orient straight north to south out of Canada. This lowers highs on Saturday back into the 40s. Fortunately, the plunge is short lived as ridging build across the area Sunday enabling the flow of warm Gulf air back into the region sending temperatures on another climb early next week. && .AVIATION /18Z TAFS THROUGH 18Z WEDNESDAY/... Issued at 1118 AM CST Tue Mar 5 2024 MVFR cigs are expected to scatter out at the TAF site btn 20Z-21Z (except STJ which will sct right around the TAF valid time). Otrw...expect VFR conds with bkn high clouds thru the remainder of the TAF cycle. Winds will be out of the north around 10kts to begin the TAF pd but will veer to the NE and diminish to around 5kt aft 03Z. && .EAX WATCHES/WARNINGS/ADVISORIES... MO...None. KS...None. && $$ DISCUSSION...Pesel AVIATION...73