626 FXUS63 KEAX 080840 AFDEAX AREA FORECAST DISCUSSION National Weather Service Kansas City/Pleasant Hill MO 340 AM CDT Tue Oct 8 2019 .Discussion... Issued at 340 AM CDT TUE OCT 8 2019 Primary forecast focus is on the strong cold front late week. Key Messages 1. Strong cold front arriving Thursday. Showers beginning early Thursday, with thunderstorms possible in the afternoon and evening, as the front moves into and across the region. 2. A few strong to severe storms may occur Thursday afternoon and evening. Isolated dime to quarter size hail and isolated gusts, 50 to 60 mph, are possible. Brief heavy rainfall is possible, with widespread amounts through Thursday between a quarter of an inch to an inch and a half. 3. First freezing temperatures of the season are possible for north- northwestern Missouri and northeastern Kansas Saturday morning. Through Wednesday, seasonable early October temperatures will persist, making for a pleasant period of weather through midweek. Highs will be in the low to mid 70s daily, with brisk morning lows. A stout 500mb trough will churn over the northern rockies toward the high plains into Wednesday. This will increase southerly return flow from the Gulf across the central Plains and Midwest. Associated with the parent trough, a strong surface front/trough will develop. Ahead of this boundary, isentropic ascent will provide enough forcing for low chances of scattered showers late Wednesday into early Thursday morning. Through Thursday, strong warm air advection will continue through the morning as surface gradient strengthens from Oklahoma into Kansas ahead of the frontal boundary. Guidance suggests pwat values will breach 1.00 in to near 1.50 inches. This would be well above average and into the 90th percentile for the time of year, based off the TOP sounding climatology. Expect scattered showers and isolated bouts of thunder to be ongoing through sunrise Thursday. With little hope of diurnal heating given cloud cover, temperatures and instability will be dependent on the strength of the WWA. Overall, mid-range guidance suggests a ribbon of 1000 to 1200 J/Kg SBCAPE could develop by mid to late afternoon. Looking at soundings, storms will be elevated and the severe concern will be conditional given the skinny cape profiles. Still, decent 30 to 40 kts of deep layer shear, primarily speed shear aloft, could be enough to support some isolated dime to quarter size hail and gusts approaching 60 mph in the strongest storms. Overall, the severe threat will be better supported farther south, into southeast Kansas/southwest Missouri and Oklahoma; the farther south the better chance for surface based convection along the tail end of the front. The bigger story with this front will be the first dose of colder fall temperatures of the season. Throw the diurnal temperature trend out the window, we could see midnight highs Friday, with day time temperatures struggling to get out of the mid to upper 40s across the area. Overnight, temperatures will dip into the 30s through Saturday morning, with lows in north-northwestern Missouri and northeastern Kansas likely dipping at or just below freezing for the first time this season. Freeze or frost products will likely be issued later this week. Fall-like weather will persist through the weekend, with highs in the 50s and 60s. && .Aviation...(For the 06Z TAFS through 06Z Tuesday Night) Issued at 1145 PM CDT MON OCT 7 2019 VFR conditions are expected to prevail through the period. Light south winds will persist, gradually increasing mid to late morning. && .EAX WATCHES/WARNINGS/ADVISORIES... KS...NONE. MO...NONE. && $$ Discussion...Kurtz Aviation...Kurtz