textproduct: Kansas City/Pleasant Hill

KEY MESSAGES

- Much above normal temperatures Monday - Tuesday. Record highs most at risk on Monday, but within reach on Tuesday as well. - Monday Record High Temperatures: MCI: 77 in 2021 STJ: 76 in 2021

- Strong to severe storms possible Tuesday afternoon - overnight. - SPC Slight and Enhanced Risks over portions of the area. - WPC Slight Risk for Excessive Rainfall

UPDATE

Issued at 248 AM CDT Mon Mar 9 2026

Local Thoughts on SPC SWODY2 Outlook:

The Enhanced Risk was pulled/expanded westward which covers more of Central Missouri (our eastern CWA). 00z and 06z model runs (especially the RAP) have deepened the surface low that will move across the eastern Plains and lower Missouri River Valley supported by the H5 closed-low ejecting out of the southern Plains and a short- wave with stronger mid-level vort maxima moving across the Northern Plains. This pushes the warm front northward into Iowa, though far northwest Missouri likely misses out on this. Strong surface pressure falls through Tuesday afternoon should increase convergence, and strong jet streak and associated dCVA should provide lift late afternoon into the evening. The 00z and 06z RAP has been hinting at a few hours of H5 height rises through the afternoon on Tuesday, which may provide enough subsidence to substantially thin out cloud cover if not provide complete breaks allowing for stronger insolation. Further, 850-700mb flow appears to be more southwesterly ahead of the southwestern trough ejecting, positioning a strong EML over the region by mid afternoon on Tuesday, while flow near the surface will be more southerly allowing plenty of moisture transport from the Gulf. As a result, projected CAPE values have been increasing across the warm sector with this system, but so has the strength of the cap given the more prominent EML. This still leads to uncertainty if there will be robust updraft initiation Tuesday afternoon. If there is enough lift to break through the cap, a supercell storm mode will be supported by the background kinematics presenting all hazards. Picking a few model soundings, the strong EML and elongated mid and upper-level hodographs standout the most for the mid and late afternoon hours. This would suggest large hail potential, around 2" or larger, along with damaging winds. The tornado threat during the afternoon is not as clear. SRH values are higher given the amount of low-level shear that is present ahead of this system and deepening cyclone, but for most of our forecast area, surface winds remained more veered, and low-level vorticity more crosswise than streamwise. From northeast Missouri and into Central Illinois is where more backing and better low-level vorticity could support a greater a tornado threat. However, if the southern Plains H5 low opens up and starts to lift earlier and shifts the surface cyclone track, enhanced area of surface pressure falls or changes in the warm front position could help to back winds and change the low-level shear environment. Similar to the Friday-Saturday event, there is higher confidence in convection once the primary cold front moves across later in the evening, with better forcing and shear present. This would primarily be a wind threat. Current 0-3km bulk shear orientation does not favor mesovort generation at this time. As the cold front moves through, attention may actually turn more to hydro/flooding. 850- 300mb mean flow is parallel to the cold front, favorable for training storms. And as mentioned in the evening shift's discussion, PWAT values are very high already, which could lead to flooding especially if we see any 1.00+ inch per hour rainfall rates.

DISCUSSION

Issued at 1228 AM CDT Mon Mar 9 2026

A zonal polar jet is situated across the northern CONUS/ southern Canada, with the sub-tropical jet moving along the base of a closed upper-low off the northern Baja California Peninsula. This pattern is allowing southwesterly low-level flow and warm advection into the local area. Temperatures should be able to climb another 5-10 degrees on Monday with highs in the 70s expected across the area.

This flow regime will eventually begin to pull Gulf moisture northward into the area late Monday and especially into Tuesday. The closed upper-low will begin move eastward Tuesday and that will help moisture surge northward in the area, resulting in dewpoints climbing into the mid 60s ahead of a stalled front. Temperatures are forecast to climb into the lower 80s, but this could be tempered some by increasing low-level cloud cover. Regardless, ample instability is likely to build during the day with MLCAPE values near or exceeding 2500 J/kg. This will be held in check initially by a strong EML. Increasing mid and upper-level flow will lead to a favorable shear environment with 35-45 kts of 0-6km bulk shear forecast. Strongly veered surface and low-level flow will limit helicity values for this event, limiting the potential for tornadoes. But with steep mid-level lapse rates and favorable shear, supercells with large hail and damaging winds look possible before storms congeal. Additionally, storms may be tied to the front with storm motions along the front. This sets up the potential for training storms and increases the potential for heavy rain and flash flooding. With flow roughly parallel to the boundary, it progresses southward very slowly. While this will be modified by any cold pool that develops, it suggest that overall, a slow southerly progression to convection will occur as the convection weakens into the overnight. Precipitable water values will also be very high for this time of year with NAEFS percentiles in the 99.5 range and 3 standard deviations above normal. Given the setup, a flood watch may be needed for this event as well.

That front finally pushes south of the area Wednesday morning with cooler air spilling into the region. Highs Wednesday will likely be 25-30 degrees cooler than on Tuesday, which actually just drops us back to normal levels for this time of year. The remainder of the extended looks fairly quiet as the polar jet remains well north of the region. The next chance for precipitation comes next weekend when a trough moves through the Northern Plains and helps to push a front southward into the area.

AVIATION /12Z TAFS THROUGH 12Z TUESDAY/

Issued at 548 AM CDT Mon Mar 9 2026

VFR conditions expected through the TAF period. Pressure gradient will increase in strength today. Also expecting boundary layer mixing to boost southwesterly wind gusts to near 20 kts during the middle of the afternoon. The winds will diminish with sunset. Increase cloud cover expected early Tuesday, but most of the ceilings occur outside of the current 12z TAF period.

EAX WATCHES/WARNINGS/ADVISORIES

MO...None. KS...None.