textproduct: Topeka

KEY MESSAGES

- Thunderstorm chances increase Saturday afternoon, with the most widespread storms and heavy rain potential Saturday night into Sunday. Strong to severe storms and flooding remain possible.

- Confidence is higher in a Saturday night into Sunday morning MCS bringing heavy rain and strong/severe storms than in any isolated Saturday afternoon development, which remains more conditional on cap erosion.

- Storm and heavy rain chances gradually diminish Sunday night into Monday as the front pushes east. An active weather pattern remains into next week.

DISCUSSION

Issued at 242 PM CDT Fri Jun 19 2026

Early this afternoon, water vapor imagery and upper air analysis continue to show a broad upper trough across the mid Mississippi Valley with a low amplitude ridge over the western CONUS, maintaining northwest flow aloft across the central Plains. Southerly return flow has developed across central and eastern Kansas, allowing low level moisture to gradually increase. Skies are mostly sunny to partly cloudy with temperatures in the 80s and dewpoints climbing into the low 60s. A weak upper-level wave moving out of Nebraska is producing some showers and thunderstorms. This activity is entering northern Kansas and is expected to slowly push southeast through the afternoon and early evening. Moisture return and a strengthening low- level jet may keep scattered showers and isolated storms going through the night, despite meager forcing aloft.

The pattern becomes more active Saturday afternoon and especially Saturday night as a stronger upper level shortwave ejects out of the western trough into the central Plains and a cold front pushes southeast toward eastern Kansas. Global guidance (including recent GFS and ECMWF runs) continues to focus a corridor of deep moisture and instability from the southern Plains into Kansas along and south of this front. Recent model trends show some spread in how quickly storms initiate and where the MCS tracks overnight. The GFS is more aggressive with daytime convection and faster at pushing storms into the area, while the ECMWF favors a more nocturnal ramp up with better lift as the main wave arrives. CAMs keep scattered showers and storms going through most of the day Saturday and then have the main MCS blowing through overnight. CAMs have also been trending slightly further south with the track of the MCS (bringing it along/south of I-70), especially compared to what the global models are depicting. Given lingering capping and modest large scale ascent during peak heating, convection through most of Saturday still appears conditional, with the highest confidence in more robust development Saturday night as the low level jet strengthens and the upper wave approaches. If we can clear out Saturday afternoon and a discrete storm breaks the cap it could become severe, with all hazards possible.

The main threat for severe storms arrives with the MCS Saturday night. An MCS is expected to develop across western Kansas and move into central/eastern Kansas after midnight Saturday night. Damaging wind gusts up to 75 mph and a few quick QLCS tornadoes cant be ruled out if the MCS maintains its strength this far east. Heavy rainfall remains a significant concern Saturday night into Sunday as storms become more widespread and rainfall rates over an inch an hour will be likely. The Weather Prediction Center highlights most of central Kansas in a moderate risk for for heavy rainfall and flash flood potential this weekend. Storm total rainfall on the order of 1.5 to 3 inches is appearing likely across much of the area. Several inches more than that are possible where storms repeatedly track over the same locations. Showers and thunderstorms are likely to persist into at least part of Sunday as the front slowly shifts east across the area and the upper wave lifts through the region. While instability should gradually wane with time and cloud cover, some strong storms and additional pockets of heavy rain remain possible during the day, and any additional rainfall will fall on increasingly saturated soils, maintaining a flooding risk into Sunday. By Sunday night into Monday, the front is expected to migrate farther east with large scale subsidence building in, leading to decreasing shower and storm chances from west to east.

AVIATION /00Z TAFS THROUGH 00Z SUNDAY/

Issued at 615 PM CDT Fri Jun 19 2026

VFR conditions expected to hold through the period. Showers near terminals are forecast to wane over the next couple of hours with the potential for scattered showers to redevelop overnight. Coverage remains uncertain, so maintained a PROB30 group from 05-11z. Chances for any TS are low (<15%). Dry time is likely through much of the day Saturday, although can't rule out a pop-up shower or storm Saturday afternoon. Low chance for MVFR cigs Saturday morning; input a scattered group to account for this potential until confidence increases.

TOP WATCHES/WARNINGS/ADVISORIES

Flood Watch from Saturday evening through Sunday afternoon for KSZ008-KSZ009-KSZ010-KSZ011-KSZ012-KSZ020-KSZ021-KSZ022-KSZ023- KSZ024-KSZ026-KSZ034-KSZ036-KSZ038-KSZ039-KSZ040.