textproduct: Topeka

KEY MESSAGES

- A cold front is expected to move through Tuesday shifting winds to the north and bringing cooler weather to the region.

- Showers and thunderstorms are likely (50-90%) Tuesday night through Wednesday night. There could be some localized heavy rainfall.

- Another round of showers and thunderstorms is forecast Friday and into Saturday.

DISCUSSION

Issued at 205 PM CDT Mon Mar 30 2026

A near zonal pattern was noted over the Great Plains per the 19Z water vapor imagery. Elsewhere shortwave energy was seen over the Canadian Rockies and another wave was noted off the west coast. Surface obs placed a low pressure system near southeast SD with a trough extending south into the southern high plains. This has kept south and southwesterly winds across the forecast area with warm and moist air advecting north.

For tonight forecast soundings suggest the boundary layer will remain capped along the surface trough this far south. And the latest CAMs keep any convective initiation well north of the state line across IA. So have a dry forecast going for tonight and into Tuesday morning. A decent pressure gradient overnight is expected to keep gusty south winds across the area and limiting how much we cool off. Because of this have tweaked the low forecast up with readings expected to be in the lower to middle 60s. This boundary is progged to slide south through the day Tuesday with winds shifting to the north. Again an EML is progged to keep the boundary layer capped through much of the day. However by the late afternoon/early evening, there is a better signal from the models for isolated to scattered convection developing along the front in large part to low level convergence. The NBM has some pretty high POPs Tuesday evening across the southeastern counties and initially I thought of capping POPs at 70 percent. But the high POPs were supported by the combined GFS/ECMWF/Canadian ensembles as more than 70 percent of the ensembles were developing measurable precip. So opted to keep the NBM pops as is.

There is a good signal for precipitation with shortwave energy lifting out Wednesday afternoon and Wednesday evening and have continued with the categorical POPs from the NBM. The main concern with storms will be whether they can strengthen to severe levels. Much of the machine learning output for severe probabilities seem to focus the better risk south of the forecast area across the southern plains. And the NAM and GFS show marginal surface based instability into east central KS. So it is something to keep an eye on but feel like the marginal risk is appropriate based on the 12Z models. There is also a concern for localized flash flooding Wednesday night with some of the models showing the potential for a narrow band of 2+ inches of rain.

The next chance for showers and storms looks to be Friday afternoon and into Saturday morning as an upper low lifts into the norther plains. Cluster analysis of the 00Z ensembles shows some timing differences with the system and lower confidence in timing thunderstorms and their intensity. However the machine learning output is showing a signal for severe weather somewhere from the Ozarks to eastern KS. Again the NBM looks pretty reasonable with it's POP forecast and haven't made any changes. Things should dry out by Saturday evening with dry and seasonal weather forecast for Sunday.

AVIATION /00Z TAFS THROUGH 00Z WEDNESDAY/

Issued at 545 PM CDT Mon Mar 30 2026

VFR at terminals as we monitor another evening of strong low level winds peaking near 60 kts at 2kft. While sfc south winds may be more mixy compared to last night, the weak sfc inversion trying to set in along the river valley coupled with a stronger LLJ led to adding in the LLWS. FROPA approaches KMHK near 16Z and 18Z at KTOP/KFOE as gusty winds veer to the north as lower clouds increase in the afternoon.

TOP WATCHES/WARNINGS/ADVISORIES

None.