textproduct: Topeka

KEY MESSAGES

- Dry and pleasant today before rain chances increase Thursday and again by the weekend.

- Gradual warming trend is expected through the weekend before a cold front and widespread rain chances early next week.

DISCUSSION

Issued at 306 AM CDT Wed Sep 23 2026

Mid-level water vapor imagery this morning shows several areas of upper-level moisture with the main swath moving northeast out of the Baja California region. This is all in response to the deepening trough over the western CONUS and will act to largely influence the weather across the central Plains over the coming days. Through the day today, lee cyclogenesis will strengthen across eastern Colorado in response to the approaching trough and begin to shift surface winds back towards the east/southeast across Kansas. Dry air advection under the easterly flow should give way to mostly clear skies by the afternoon and lead to a very pleasant afternoon. Expect highs in the 70s by peak heating hours.

By this evening and into Thursday morning, shortwave vorticity advection embedded in the southwesterly flow increases across western and central Kansas. Rain chances will become widespread across central/north-central KS through Thursday morning with chances decreasing towards eastern Kansas. Isentropic ascent and mid- level lift should begin to slide east Thursday night into Friday morning as the main western trough axis pushes into the central Plains and shunts the southern upper ridge back towards the Gulf. PoPs should increase across much of eastern Kansas during this time with some rumbles of thunder accompanying showers. Ensemble probabilities of rainfall totals exceeding 1 inch range between 40- 75% from Topeka to Concordia respectively. Areas further east, generally around the I-335 corridor have around a 20-30% probability of seeing 1 inch of rainfall.

Widespread rain chances begin to decrease by Saturday afternoon as the compact shortwave trough axis slides east into Missouri with mid- level ridging building in from the west as we head into Sunday. A brief warm-up can be expected under this ridge Sunday into Monday as high temperatures build back into the mid to upper 80s. This should be short-lived as long range guidance has decent agreement in a strong trough moving across the central US by Tuesday and Wednesday. Another widespread chance for rain/storms should accompany this strong upper system as cooler air builds back in from the north for the remainder of the week.

AVIATION /12Z TAFS THROUGH 12Z THURSDAY/

Issued at 542 AM CDT Wed Sep 23 2026

Low-end MVFR and some patchy IFR ceilings will continue over the first few hours of the TAF before beginning to scatter out. Expect VFR conditions to develop by late morning to early afternoon and continuing through the period with light easterly winds.

TOP WATCHES/WARNINGS/ADVISORIES

None.