textproduct: Kansas City/Pleasant Hill

KEY MESSAGES

- Showers and thunderstorms continue across the region this morning, with locally moderate to heavy rainfall possible.

- Severe thunderstorms are likely late afternoon into late tonight.

- Far NW Missouri and NE Kansas will be under the greatest threat for all severe hazards by late afternoon and early evening.

- Storms should congeal into a line of thunderstorms by this evening, and move east southeast through the region late tonight. Once this occurs, damaging wind gusts should become the primary hazard, but a few brief tornadoes may be possible.

- Moderate to heavy rain will be possible again with the storms tonight. A flood watch is in effect through almost the entire CWA through 7 AM Tuesday.

- Cooler temperatures arrive for Tuesday through Thursday before heating up once more by this weekend.

DISCUSSION

Issued at 331 AM CDT Mon May 18 2026

A mature mesoscale convective system (MCS) is moving through the CWA this early morning, with a few sporadic 50 to 60 mph wind gusts as well as relatively widespread 1+ inches of rain (isolated pockets have received a bit over 2"). The leading convective portion of the MCS will continue to move off to the east southeast through the next few hours, with CAM guidance suggesting convection stalling out toward the northern edge of the Ozark Plateau by later this morning and continuing into the afternoon hours. With around 1.8 to 1.9" PWATs in this region and the potential for a prolonged period of moderate rainfall, WPC has upgraded the new Day 1 excessive rainfall outlook to a moderate for Linn County KS into Bates and Henry County MO (although 00z SPC HREF guidance keeps the corridor of heaviest rainfall just south of our CWA toward the Lake of the Ozarks and surrounding areas).

Attention then turns to the severe and heavy rainfall threat later tonight as the mid/upper trough moves out of the Four Corner regions and ejects across the Central Plains this afternoon and evening with strengthening WSW deep layer flow overspreading the region. Recent CAM guidance suggests that convective initiation should occur by mid to late afternoon along the stalled or slow moving northeast to southwest oriented front across western IA into SE Nebraska and NE Kansas within an environment characterized by moderate to high instability and 40+ knots of deep layer shear. The window for discrete storms will likely be fairly small as deep layer shear vectors are generally parallel to the front, allowing for upscale growth into clusters or line segments. The greatest threat for all severe hazards will be late afternoon/early evening across far NW Missouri (Atchison, Holt, and Nodaway) and NE Kansas (Doniphan) where storms could remain relatively discrete initially. A well developed line is projected to develop along the front by later this evening across NW Missouri into NE Kansas, moving to the east southeast through the late evening hours into late tonight, at which point severe wind gusts should become the primary hazard, although with strong low level bulk shear there will be a threat for QLCS mesovortices, especially considering CAM guidance suggests the potential for bowing segments tonight. In addition to the severe threat, locally moderate to heavy rainfall will be possible yet again with PWAT values ranging from 1.6 to 2". Due to the threat for heavy rainfall this morning and again late tonight, have decided to expand the flood watch to almost the entire CWA through 7 AM Tuesday morning.

Cooler temperatures and much more comfortable dew points are expected for Tuesday through Thursday, with daily afternoon highs in the mid to upper 60s. There will be a 40 to 50% chance for showers and storms Thursday afternoon and evening, but severe weather is not anticipated. Warmer temperatures and increasing moisture return should arrive by Friday and into the weekend.

AVIATION /12Z TAFS THROUGH 12Z TUESDAY/

Issued at 632 AM CDT Mon May 18 2026

Scattered showers and thunderstorms continue across the region this morning. These should come to an end at STJ by around 14z and the KC metro terminals by around 16z. SSE winds should increase with gusts up to 30 knots by later this morning, continuing through the afternoon hours. A line of severe thunderstorms is likely to impact STJ between roughly 00z and 03z tonight, moving through the KC metro terminals between 02z and 05z tonight. Severe wind gusts will be possible along the leading edge of the line, with periods of moderate to heavy rain reducing VIS significantly. Stratiform rain with perhaps a few lightning strikes may linger behind the main convective line into early Tuesday morning. MVFR CIGs are likely by around 6z Wednesday morning.

EAX WATCHES/WARNINGS/ADVISORIES

MO...Flood Watch through Tuesday morning for MOZ001>007-011>016- 020>024-028>032-037>040-043>046-053-054. KS...Flood Watch through Tuesday morning for KSZ025-057-060-102>105.