textproduct: Topeka

KEY MESSAGES

-Strong storms form near I-35 this afternoon as a cold front advances southward.

-More wet weather returns this weekend, with a risk for a few severe storms and flooding.

DISCUSSION

Issued at 155 PM CDT Wed Jun 17 2026

A cold front, currently moving across I-70 at the moment, will continue to quickly push to our south. Ahead of the front, dewpoints in the low to mid 70s are combining with temperatures in the low to mid 90s and heat indices in the low 100s are common as a result. By 4pm, the cold front will accelerate southward roughly along and just south of the I 35 corridor. Strong heating and rich boundary layer moisture will support MLCAPE in the 30004000 J/kg range with 4550 kt of deep-layer shear, placing the area in a favorable environment for organized convection along the boundary. Forecast soundings from the RAP and HRRR depict an inverted V profile and DCAPE values near 1500 J/kg, suggesting a primary threat of damaging winds from any stronger downdrafts in addition to large hail in initial updrafts. While the most concentrated severe threat may focus east of the forecast area where forcing and shear are maximized, storms that develop in east central Kansas late this afternoon and early evening could still produce severe wind gusts and hail, with a conditional low-end tornado risk near any remnant boundaries before the front undercuts the convection. Coverage this afternoon is expected to be scattered, with convection initiating on the front and possibly on pre-frontal convergence axes where mixing is stronger. Storm motion will be generally east-southeast, and any cell mergers or short line segments will be capable of producing pockets of heavier rainfall, though progressive storm motions should limit the flood threat tonight. Thunderstorm chances decrease from northwest to southeast this evening as the front slips south and instability is exhausted, with most activity shifting toward Missouri and southeast Kansas by late evening.

Behind the front, cooler and drier air filters into the area for Thursday and Friday. High temperatures will fall back closer to seasonal normals with lower humidity, as surface high pressure builds into the central Plains and weak northwest flow persists aloft. This should provide a mainly dry period Thursday through at least Friday for much of northeast and east-central Kansas, aside from low chances for some elevated showers tomorrow as a weak mid-level wave swings through. Attention then turns to the weekend as westerly flow aloft and southerly moist surface flow develops. Model consensus indicates increasing southerly low-level flow and moisture transport back into Kansas by Saturday, with precipitable water values climbing to above early-summer climatology (~2 inches). This pattern favors one or more rounds of showers and thunderstorms from Saturday into Sunday. Given the deeper moisture and stronger synoptic forcing, storms this weekend will be capable of producing locally heavy rainfall, and WPC highlights the central Plains into the Midwest for areas of excessive rainfall during this time frame. Confidence is increasing that parts of the area will see at least a few inches of rainfall. Additionally, moderate instability and shear suggest a few storms could again be strong to severe, though mesoscale details regarding boundary placement and timing of shortwaves remain uncertain at this lead time.

AVIATION /00Z TAFS THROUGH 00Z FRIDAY/

Issued at 633 PM CDT Wed Jun 17 2026

VFR at terminals as the front has passed well south of terminals. Gusty north winds subside by 02Z. Additional disturbance brings scattered showers and embedded TS aft 10Z through the morning period. With the higher cloud bases(~9kft) and better forcing south of terminals, confidence is low in TSRA impacts, but will monitor trends this evening.

TOP WATCHES/WARNINGS/ADVISORIES

None.