textproduct: Kansas City/Pleasant Hill

KEY MESSAGES

- Hazardous heat continuing through the weekend and into parts of next week. An Extreme Heat Warning remains in effect areawide until 8 PM Saturday and for counties generally along and south of US-36 until Sunday at 8 PM. The Kansas City Metro and surrounding counties remains under an Extreme Heat Warning until 8 PM Tuesday.

- Showers and storms will be possible (30-50% chance) Sunday afternoon and evening. The highest chances are in northern Missouri.

- Marginal Risk (Level 1 of 5) for severe storms capable of damaging wind gusts and hail.

DISCUSSION

Issued at 327 PM CDT Sat Sep 5 2026

The Omega-block pattern will remain the focal point of the short- term forecast with little changes to overall upper-level flow in the last 24 hours or so. Peak heating is expected to resemble that of yesterday given a lack of any other potential limiting factors. Just before 9 AM Saturday, several sites across the region had already started reporting heat index values in the upper 80s and lower 90s. Given the fact that several sites were comfortably overachieving forecast temperatures by 3-5 degrees this morning, afternoon temperatures and highs were nudged up slightly. With temperatures climbing into the upper 90s as we progress through the afternoon, we could see widespread heat index values of 105F across much of Missouri and far eastern Kansas. Some locations may be able to surpass this 105F threshold, primarily those in our southernmost counties where there's a 60-80% chance of air temperatures hitting or exceeding 100F.

With a backdoor cold front moving through overnight, temperatures across northern Missouri are expected to top somewhere in the upper 80s (NE MO) or low/mid 90s (NW MO). This temperature reduction looks to prevent widespread triple digit heat index values, and so the Extreme Warning for these portions of the state will come to an end around 8 PM today. Unfortunately, not all will be able to reap the benefits of this "cold" front tomorrow as recent guidance has this boundary coming to a halt generally north and west of the Missouri River. As the day progresses, the front should begin to creep to the southwest, but it doesn't appear to be early enough to mitigate the effects of diurnal heating. Temperatures in the mid/upper 90s are currently forecast along and south of the I-70 corridor on Sunday, but if the front is able to surge further south earlier in the day, it could prevent these maximum temperatures from being realized.

Another consideration for Sunday is the potential for showers and thunderstorms to develop in the afternoon and evening hours. Cooling mid-level temperatures and steepening lapse rates ahead of the boundary may permit scattered air-mass thunderstorm development in a strong warm-air advection regime. Generally speaking, most storms should be your run-of-the-mill ordinary thunderstorm, but forecast soundings adopt a noteworthy inverted-V shape so downburst winds are certainly not out of the question. It's possible we could also see a few stronger updrafts conducive of hail production but am not as convinced on that threat as of yet. CAMs draw in additional convection from the Northern Plains during the evening hours though it's unclear how this may evolve in our area with worsening instability...current thinking is that any convection that does move in from the north will rapidly lose intensity after sunset, though strong wind gusts may be possible initially. SPC has highlighted much of the CWA in a Marginal Risk (Level 1 of 5), encompassing both of these possibilities. Overall, there's about a 30-50% chance of showers/storms across northern Missouri Sunday evening. Further south and east, probabilities are lesser at around 20-30%.

The backdoor cold front will have completed its journey through the CWA by Monday morning. This should result in somewhat cooler conditions across the region, especially in central portions of Missouri, hence the portion of the Extreme Heat Warning extending from St. Joseph to Boonville will end at 8 PM on Sunday. A third section of the Extreme Heat Warning that includes the Kansas City Metro will be allowed to remain in effect until Tuesday evening at 8 PM. Conditions on Monday in the vicinity of the Kansas City Metro and south appear borderline enough to warrant the continuation of the warning for now, especially considering the widespread Major (Level 3 of 4) and Extreme (Level 4 of 4) HeatRisk despite slightly lesser temperatures and heat index values. Moreover, heat is expected to recover on Tuesday, extending the already prolonged heat event. Uncertainty still exists in regards to Wednesday as the thermal ridge collapses and a low-pressure system marches along the northern US border. This system will bring another cold front through the region, but the timing of the frontal passage will dictate whether heat headlines need to be extended through Wednesday or not. As this frontal passage is better resolved in the guidance, a decision will be made on whether an extension is necessary. To end the week, expect closer to normal temperatures in the mid/upper 80s and low 90s in addition to more shower and storm chances as shortwaves snake through a more zonal pattern.

AVIATION /18Z TAFS THROUGH 18Z SUNDAY/

Issued at 100 PM CDT Sat Sep 5 2026

VFR conditions are expected through the period with only some passing high level clouds. Light (5 knots or less) and variable winds are expected through the period.

EAX WATCHES/WARNINGS/ADVISORIES

MO...Extreme Heat Warning until 8 PM CDT Tuesday for MOZ028-029-037- 043-053. Extreme Heat Warning until 8 PM CDT Sunday for MOZ020>022-030- 031-038>040-044>046-054. Extreme Heat Warning until 8 PM CDT this evening for MOZ001>008-011>017-023>025-032-033. KS...Extreme Heat Warning until 8 PM CDT Tuesday for KSZ025-057-060- 103>105. Extreme Heat Warning until 8 PM CDT Sunday for KSZ102.