textproduct: Topeka

KEY MESSAGES

- A cold front has stalled and will retreat back north on Wednesday afternoon and evening

- The elevated thunderstorms will end during the mid morning hours.

- Thunderstorms become likely late this afternoon, with some severe storms especially in the late afternoon and evening hours. Hail is the primary hazard. If the warm front is able to move back north, then the hazards will include damaging wind gusts and possibly a few tornadoes.

- Friday features another chance for strong to severe thunderstorms.

DISCUSSION

Issued at 346 AM CDT Wed Apr 1 2026

Early this morning, water vapor satellite imagery showed a southern stream upper level trough across the southwest US. An amplified northern stream upper level trough was digging southeast towards the Northwest Pacific coast. An upper trough was moving east across the Great Lakes.

The 6Z surface map, showed a surface cold front extending from western Lake Erie, west-southwast across southern IL, then southwest across central MO, into southeast KS, and southwest across the central OK into west TX. North of the boundary isentropic lift was causing scattered showers and elevated thunderstorms across the central, northeast. and southeast counties.

Today through Thursday:

The scattered showers and elevated thunderstorms will continue through day break, as the front shift farther south the steeper isentropic surfaces may occur farther south as well. Most of area will have light rain or drizzle with northeast winds keeping highs in the mid to upper 50s north, to lower to mid 60s across the remainder of the CWA.

Almost every CAM now holds the front nearly stationary across southeast KS through the early evening hours. As the DCVA overspreads the CWA we will see rain and elevated thunderstorms redevelop this evening and move northeast across the regions. The MUCAPE will increase to 1200-1500 J/KG across central, east central and portions of northeast KS. Therefore, this evening the elevated storms with 40 KTS of effective shear could produce severe hail. If the elevated storms rotate this evening, they may produce larger hail up to half dollars up to 2 inch size.

The stationary front will eventually lift north as warm front across the eastern half of the CWA during the evening hours and early morning hours of Thursday, as a surface low over western KS moves northeast into southeast NE by 12Z THU. A cold front will then push southeast across the CWA during the mid morning hour of Thursday. A line of showers may develop but the richer moisture will shift east of the area before 12Z as the low-level wind veer mover to the southwest. The stronger ascent ahead of the H5 trough will shift northeast into MO and IA after 12Z THU.

The deterministic models such as the ECMWF and GFS show the front lifting north a bit faster, and if the front were to reach the southeast or east central counties of the CWA, then surface based storms may develop along and south of the front. These storms may initially be supercell thunderstorms that will congeal more into a line of storms during the evening hours. If a discrete supercell were to move along the warm front then the enhanced baroclinic horizontal vorticity could be tilted and stretched by a storm's updraft. But I'm leaning towards the CAM solutions, keeping the warm front farther south across southeast KS during the afternoon and early evening hours.

Training of elevated storms north of the warm front across east central KS may lead to localize flooding late this afternoon and through the evening hours. Not real certain where this line of elevated storms will set up. Several of the CAMs show the training of elevated storms to be along I-35 during the late afternoon and evening hours.

The SREF shows the a 80 to 90 percent chance of 2+ inches of rainfall through Thursday morning for areas along and southeast of I-35. There may be higher totals if training of elevated thunderstorms occur across the southeast counties of the CWA. The heavy rainfall may lead to some flooding of rivers and low- lying areas.

The showers and thunderstorms should end from west to east across the CWA during the late morning and early afternoon hours. Skies will clear Thursday afternoon and highs will reach the mid 60s north to the lower to mid 70s south. An H5 trough will move onshore across the Pacific northwest.

Thursday night through Saturday:

The extended range models are in agreement, forecasting the H5 trough over Pacific northwest to dig southeast across the central Rockies by 12Z Friday. The H5 trough will then lift northeast across the northern and central Plains. A cold front will push southeast across the CWA Friday afternoon. The big question is how much richer Gulf moisture will return ahead of the front. The richer moisture may only make it back to portions of the east central KS, ahead of the front where a line of thunderstorms may develop during the afternoon hours. These storms may be strong to severe with the primary hazard being large hail and damaging wind gusts. This line of storms should move east of the CWA by 12AM Saturday. Highs on Friday will be warmer ahead of the front reaching the mid to upper 70s. The northwest counties will be cooler in the 60s.

Saturday through Wednesday:

Expect cooler weather as the mid level flow becomes northwesterly and a surface high pressure ridge builds southward across the eastern Plains and Mid MS River valley. Saturday highs will be the coldest, with mid 50s north and mid to upper 50s south. Lows Saturday night may fall below freezing across the area.

Sunday's highs will be in the upper 50s far east to lower to mid 60s across the remainder of the CWA.

Monday, we may warm back up into the upper 60s to lower 70s, before another front moves southeast across the area Monday night.

Highs Tuesday will be in the lower to mid 60s.

By Wednesday, the mid level flow will become zonal and highs will reach the lower to mid 70s.

AVIATION /12Z TAFS THROUGH 12Z THURSDAY/

Issued at 633 AM CDT Wed Apr 1 2026

The ceilings are dropping, KFOE now down to IFR, and KTOP and KMHK down to MVFR. I expect KTOP and KMHK ceilings to drop down to IFR in the next few hours. The terminals will keep IFR ceilings until 00Z, then scattered elevated thunderstorms will move across the terminals and ceilings will rise back to MVFR levels. Expect northeast winds to veer to the east through the afternoon but remain around 10 KTS with some minor gusts. Through the evening hours, a warm front will move north veering winds to the south at 12 to 16 KTS with gusts of 20 to 26 KTS after 6Z.

TOP WATCHES/WARNINGS/ADVISORIES

None.