textproduct: Topeka

KEY MESSAGES

- A few severe storms may develop late this afternoon into the evening, with hail and damaging winds as the main threats.

- Cooler temperatures expected Friday with lingering showers and thunderstorms.

- A washout isn't anticipated this weekend, but we will likely continue to see off and on showers and thunderstorms.

- Monday and/or Tuesday could present more of a severe weather setup in the area, but plenty of uncertainty exists at this time range.

DISCUSSION

Issued at 342 AM CDT Thu Apr 9 2026

Upper air pattern depicts a low moving across southern Ontario while another larger low spins in the eastern Pacific. At the surface, the front from yesterday has settled in an east-west orientation near the I-70 corridor. Some light radar returns have been noted north of the boundary within an area of elevated instability, but no lightning has been observed yet. As we go through the morning, CAMs show some more scattered activity developing in central KS closer to sunrise and moving across northern KS through the mid to late morning hours, all while the front lifts north. The boundary looks to set itself up near the KS/NE border, probably on the NE side, by this afternoon. It's unclear how much clearing will take place through the afternoon with guidance varying somewhat on where a few showers might linger. Even so, there does seem to be decent agreement on thunderstorms becoming more favorable during the 6-10pm time frame with better convergence along the front and some weak perturbations aloft helping to provide upper-level support. The pre- storm environment has effective shear between 35-45 kts and CAPE up to 1000-1500 J/kg. Inverted-V soundings and DCAPE up to 1000 J/kg signal potential for damaging winds, and the instability and shear parameters would be sufficient for large hail with any supercells that can develop before storms congeal into a line. Can't entirely rule out a tornado if a supercell moves along the warm front, but this scenario seems unlikely given high LCLs. Later into the evening/night as storms form a line and become less organized, the severe threat should end. There could still be some locally heavy rainfall with storm motions being parallel to the front, unless the front moves south quickly enough to keep storms more progressive. Based on the latest HREF and its individual members, it would seem reasonable for locations with storms to see an inch or two of rainfall, though locally higher amounts may be possible if training of storms occurs.

Heading into Friday, the front is favored to push mainly south of the area, which would keep more of the instability and associated severe risk to our south. That said, some post-frontal showers look to linger into at least the morning. Coverage does not look widespread, however, so some dry time can be anticipated during the day. Temperatures look cooler behind the front and with clouds/rain, resulting in highs in the upper 50s to mid 60s.

The weekend doesn't have a particular time period where strong forcing is in play, as any rain chances are driven by weak perturbations within the southwest flow aloft. This keeps the chance for storms off and on, and although likely PoPs are forecast throughout those two days, there should be some breaks in the rain at times and a washout is not anticipated. The WAA should help temperatures return to the 70s. Although instability increases, shear looks weaker so confidence in severe weather is low.

The main Pacific trough comes across the western US early next week. Depending on the speed of this system and the timing of associated surface features, this could lead to a better setup for severe weather in the region Monday or Tuesday. Still plenty of time for mesoscale details such as these to be worked out in the coming days, but it will be something to watch.

AVIATION /06Z TAFS THROUGH 06Z FRIDAY/

Issued at 1240 AM CDT Thu Apr 9 2026

VFR conditions continue. Winds are borderline for LLWS conditions overnight and will continue to monitor, but opted to keep out of TAFs at this time. Otherwise, expect southerly winds to increase with 20-25 kt gusts becoming common through the afternoon, then subsiding after sunset. Thunderstorm chances increase late in the TAF period, with CAMs showing storms developing along a stalled front north of terminals in the evening and then dropping south. These may not reach TAF sites until the very end of the current period, so decided to hold off mention for now, but will likely need to consider adding in the next issuance.

TOP WATCHES/WARNINGS/ADVISORIES

None.