textproduct: Topeka

KEY MESSAGES

-Scattered afternoon storms become more widespread tonight. A few strong winds gusts and heavy rainfall are the main concerns.

-Temperatures are returning to near average instead of near records behind today's cold front.

-POPs return to the forecast with periodic chances for rain from this weekend into early next week.

DISCUSSION

Issued at 204 PM CDT Wed Sep 9 2026

This afternoon, a cold front is positioned near I-70 through the middle of our forecast area. Scattered showers and isolated storms were ongoing near the boundary. Temperatures show a large spread across the area with most locations in the 80s near and north of boundary, especially where clouds are limited. However, some locations remain in the 70s where cloud cover and rain have been more dominant. South of the front was much warmer, comparable to the last few days. These locations, mainly near and south of I-35, will experience heat index values above 100 degrees again today. Instability has also been steadily increasing throughout the day, and will continue to do so south of the front. Thus, there remains at least a low chance for a few severe storms in this area this afternoon and evening. Strong winds are the main hazard of concern given inverted V soundings and DCAPE greater than 1000 J/kg. Locally heavy rainfall could also occur with pwats of 2.0-2.2 inches.

CAMs show coverage of storms increasing late this evening and tonight as large scale ascent increases ahead of a shortwave aloft. Storms may move over some of the same areas with 850-300mb flow parallel to the cold front. Pwats will remain high so heavy rainfall will become the main concern, especially with training convection. HREF shows pockets of 2.0 to 3.0 inches of QPF along and south of I-70, and a 70 percent chance of at least 1.0 inch of rain near I-35. Still, the risk for flooding appears fairly low given the lack of recent precipitation. Three hour FFG is around 3.0 inches area-wide, so any localized flooding will likely be confined to urban areas that see heavy rainfall rates or multiple storms throughout the night.

Rain moves south along the front Thursday morning. Low clouds will clear from north to south, leaving sunshine and light winds. Temperatures will finally be near average instead of near records area-wide tomorrow afternoon, with highs in the low to mid 80s! Temps creep up slightly on Friday with stronger southerly flow. POPs then increase this weekend, but uncertainty remains on whether a complex of storms develop near another sfc boundary like long range and ensemble models show Saturday morning. Shorter range models, like the NAM, remain dry. A mid-level ridge builds in from the south, and eventually expands toward the southeastern CONUS. Long range models show a shortwave in the west/southwest flow north of the ridge Sunday afternoon, and a sfc front draped across northeastern KS early next week. That set up is keeping 30 to 60 percent POPs in the forecast through at least early next week.

AVIATION /18Z TAFS THROUGH 18Z THURSDAY/

Issued at 1230 PM CDT Wed Sep 9 2026

Complicated TS forecast this period as a cold front slowly moves through the area. For now, have maintained the PROB30 this afternoon at the Topeka airports, but radar trends may support higher chances for TS on occasion -- will amend if necessary. Beyond this afternoon, there is slightly higher confidence in TS impacting all sites tonight, mainly in the 05Z to 10Z timeframe. MVFR CIGS also appear likely as rain chances decrease toward the early morning hours of Thursday. Conditions improve to VFR late morning Thursday.

TOP WATCHES/WARNINGS/ADVISORIES

None.