textproduct: Kansas City/Pleasant Hill

KEY MESSAGES

- Lingering Storms This Morning

- Strong Storms Possible Late Tonight

- Notable Severe Weather Threat Monday

DISCUSSION

Issued at 207 AM CDT Sun May 17 2026

Strong PV anomaly over the Pacific Northwest will promote troughing into the Northern Rockies with several short-wave perturbations and compact vort maxima traversing across the central CONUS. This will keep flow southwesterly providing persistent WAA along with moisture transport, maintaining an active pattern for the next few days across the region.

Strong dCVA continues over the Front Range and High Plains of Kansas, resulting in a deepening of the surface cyclone with surface pressure falls extending into the lower Missouri River Valley. The synoptic warm front is likely located somewhere over southern Iowa during the early Sunday morning hours, though the repeated convection over Northern Missouri has released several outflow boundaries, masking most surface analysis for finding clear signs of the synoptic boundaries. As of 0630 UTC, a MCV has generated a line segment with bookend moving from northeast Kansas / southeast Nebraska into northwestern Missouri. This has been producing severe wind gusts. This will continue to ride along an remnant outflow boundary along with an environment of decent lapse rates especially above the boundary layer. The main question will be how far east does this hold together. The low-level jet has helped to amplify this line segment. As this dissipates, subtle H5 height rises Sunday afternoon should keep conditions dry, though lingering cloud cover from convective debris may still be around. However, this will change heading into the late night hours again.

Next H5 vort maxima moves across the Plains and into the forecast area late Sunday evening. Two distinct areas of stronger dCVA will concentrate to areas of surface low development, one moving into the upper Midwest and another over the High Plains and Central Plains of Kansas. CAPE values should increase beyond 2000 J/kg for western Missouri, with potential for values beyond 3000 J/kg over portions of eastern Kansas. Most of the afternoon though is expected to struggle with a capping inversion, at least for our zones. Some activity over north-central Kansas is possible shortly after peak heating, along with slightly stronger surface convergence along an axis of surface pressure falls with deepening cyclone. Eventually this activity will congeal into an MCS, with recent HRRR cycles showing a QLCS mode at least in its simulated reflectivity fields as the cold front starts to push eastward. The main question as this pushes eastward will be the deep layer shear, as stronger values may be behind the front. If the line holds strong into northeastern Kansas and western Missouri, expecting damaging winds, and perhaps a conditional tornado threat with mesovort generation if we get a favorable 0-3km bulk shear vector orientation. Even as the main line passes through, stratiform rain showers may continue to the early morning hours of Monday. Cold front is progged to stall over Central Kansas Monday morning.

This stalled boundary will pave the way for a more potent setup Monday afternoon and evening from the eastern Plains into the lower Missouri River Valley. There is a lot of uncertainty with how the mesoscale environment will evolve on Monday, and for our counties will determine if are able to break the cap on Monday afternoon and get surface based storms, or if we will need to wait for the low- level jet to kick in and provide a robust MCS of some kind. With robust destabilization, if the cap breaks in the afternoon, supercells capable of all hazards will be possible throughout the potent warm sector in eastern Kansas to northwest Missouri. Deep layer shear will drastically increase with the approach of may H5 trough and stronger jet streak. As mid and upper-level hodographs elongate, low-level shear increases as low-level jet starts up after 00-01z in the evening, increasing the potential tornado threat. Late Monday evening, discrete activity will begin to congeal, with a robust kinematic environment keeping a MCS organized capable of damaging winds. Tornadic threat will be determined by how the lower- level shear environment evolves. Certainly favorable bulk shear magnitudes will be present, but how will the shape of the low-level hodographs appear with respect to the storm motion or cold pool propagation? Our Kansas Counties are in the Day 2 moderate risk.

AVIATION /18Z TAFS THROUGH 18Z MONDAY/

Issued at 1231 PM CDT Sun May 17 2026

Gusty south winds are expected to prevail through the period. Moisture trapped below the inversion is expected to lead to low VFR ceilings this afternoon, which will gradually scatter this evening with the loss of heating. Potential for a decaying MCS to build south across the region Monday morning. Confidence is not high enough at this point to go prevailing, but could see some gusty winds with complex if it does develop.

EAX WATCHES/WARNINGS/ADVISORIES

MO...Flood Watch from late tonight through Tuesday morning for MOZ020>022. Flood Watch through Tuesday morning for MOZ001>007-011>016-023- 024. KS...Flood Watch from late tonight through Tuesday morning for KSZ025-102.