textproduct: Topeka

KEY MESSAGES

- Rounds of scattered showers and storms continue through Saturday night. Marginal risk for a few stronger storms Saturday evening.

- Rain chances increase again next week. Watching the potential for areas of heavy rain mid-week.

- Temperatures continue to be near to above average. Daytime highs in the 70s to low 80s over the next week.

DISCUSSION

Issued at 343 AM CDT Fri Sep 25 2026

An amplified upper pattern is in place across the CONUS this morning. Strong upper ridging is centered over the Upper Midwest, acting as somewhat of an Omega Block. This has helped develop two cut-off upper lows, one stronger low near the Outer Banks and a weaker one over Arizona and New Mexico. The latter low will be the focus for our weather over the next few days, as it steadily lifts northeast through Saturday, transitioning to an open wave in the process. Within the broad southerly flow ahead of the low, pockets of weak isentropic ascent will lead to brief periods of showers and weak storms. Tough to pinpoint exact timing and coverage of these, but water vapor imagery supports short range guidance showing one wave of showers/storms developing over the next few hours and moving northeast. This would likely be followed by a lull for most of the day, with perhaps some lingering very light showers. Persistent cloud cover will keep temperatures mostly in the low/mid 70s, though some spots towards central KS could approach 80 if the clouds can thin.

As the main wave approaches tonight, another round of more numerous showers/storms appears likely. Coverage should be highest towards central KS closer to the better upper forcing. Instability remains weak, but similar to yesterday any persistent areas of convection could result in localized 1-2" rainfall amounts. Expecting decreasing precipitation coverage throughout the morning as the upper wave pulls off to the north. This should allow for pockets of clearing, with temperatures climbing into the low 80s. Watching the potential for a few evening or overnight thunderstorms to develop near a weak frontal boundary. This is somewhat uncertain given subtle height rises, and possible displacement of better instability to the west. But with 25-30 kts of effective shear, any storm that does develop could produce some gusty winds or small hail.

Stronger upper ridging builds over the region Sunday into Monday. So confidence is higher in a couple of warmer and drier days. Highs should climb into the low 80s, particularly if winds can turn more southerly in the wake of Saturday night's weak front.

Attention then turns to a stronger upper low that will move across the southwest CONUS early next week before approaching the Plains mid-week. As is typical for such an upper low 5 days out, there is plenty of spread in exact track and timing. So confidence in the details is low. However guidance is very confident in a deep surge of tropical moisture ahead of the low, potentially directly tied to recurving Hurricane Polo. ECMWF ensemble mean PWATs are already approaching 2", around record values for this time of year. Coupled with the potentially slow movement of the system, we'll have to watch out for heavy rains and perhaps some flooding mid-week.

AVIATION /06Z TAFS THROUGH 06Z SATURDAY/

Issued at 1231 AM CDT Fri Sep 25 2026

First round of scattered showers has lifted northeast of KTOP. Expecting another round of showers, possibly with a few embedded thunderstorms, to develop 09-10z towards KMHK and move east towards KTOP/KFOE shortly after sunrise. Light additional showers may linger for much of the period after this, but with lower overall coverage and intensity. Ceilings look to stay primarily VFR, but some MVFR ceilings may mix in for a time, especially towards KMHK. Winds stay generally southeasterly 5-10 kts.

TOP WATCHES/WARNINGS/ADVISORIES

None.