textproduct: Kansas City/Pleasant Hill

KEY MESSAGES

- Multiple rounds of showers and storms are expected this week, especially Monday night through Wednesday across northern Missouri and northeastern Kansas. The threat for flooding is increasing, especially north of the Missouri River.

- Well above normal temperatures are likely Monday and Tuesday along and south of the I-70 corridor. Heat index values may climb into the 100 to 105 range.

DISCUSSION

Issued at 238 AM CDT Sun Sep 13 2026

It's another complex and challenging forecast tonight as quasi-zonal flow continues across the middle of the country, with stronger jet energy to our north and low-level jet fed storms across eastern Kansas this morning. Through the remainder of the overnight into Sunday morning, low-level flow will increase further north across northeastern Kansas and northwestern Missouri. This is resulting in renewed convective development from north central Kansas into northeastern Kansas. As this low-level jet, and convergence on its nose, shift east this morning, we should see showers and storms drift east as well, moving into northwestern Missouri as result. With the waning of the low-level jet during the day, precipitation should decrease with time. Tonight however, as the low-level jet reinvigorates, strong moisture transport will lead to anomalously high precipitable water values streaming into eastern Kansas and western Missouri. We should see new convective development anywhere from eastern Kansas to western Missouri, most likely in the 06Z to 09Z time frame, on the nose of the low-level jet. This corresponds to very strong isentropic ascent from the 305K surface through the 310K surface. Given all these trends, have decreased PoPs through the day, then ramp them up again tonight into tomorrow morning. While the overall threat of severe weather looks low today and tonight, can't rule out a strong storm capable of some strong winds and hail, especially tonight into tomorrow morning.

Additional rounds of showers and storms are likely through at least the middle part of the week. The setup for Tuesday night into Wednesday morning looks particularly interesting with regards to heavy rainfall. A frontal boundary is likely to stall in the area with deep flow generally parallel to that boundary. Copious amounts of moisture are transported north into the area from a strong low- level jet. This leads to precipitable water values above the 99th percentile, pushing 2 to 2.25". With deep flow parallel to the boundary, training storms are likely, and with the anomalously moist airmass in place, heavy rainfall and potential for flash flooding is becoming more likely. A large slight risk for excessive rainfall has been placed over much of the forecast area. It's possible, as confidence in placement and magnitude increase, this will be upgraded. We may need a flood watch at some point in the next day or so to account for the increasing risk of flooding rainfall. Cumulatively, the forecast continues to show widespread 3-5" rain amounts for northern Missouri, mainly north of the Missouri River.

With regards to the potential for heat, the southern portions of the forecast may see highs in the low to mid 90s Monday and Tuesday, with dewpoints climbing into the low to mid 70s. This leads to heat index values in the 100 to 105 range. It's possible a heat advisory will be needed for a portion of the forecast area Monday and Tuesday. But given the potential for storms and cloud cover, confidence is still somewhat low at this point.

AVIATION /06Z TAFS THROUGH 06Z MONDAY/

Issued at 1147 PM CDT Sat Sep 12 2026

Low confidence forecast, but forecast prevailing VFR conditions. Expect mainly dry conditions tonight into Sunday, but could see a few thunderstorms develop across southern Iowa building into northern Missouri Sunday afternoon. Light northerly flow is expected to become more easterly as surface ridge across the Northern Plains builds east into the Upper Midwest.

EAX WATCHES/WARNINGS/ADVISORIES

MO...None. KS...None.