Area Forecast Discussion

KEY MESSAGES

- Expect a few isolated thunderstorms to develop this afternoon into tonight near a passing cold front.

- Additional chances for showers and thunderstorms are expected, particularly Sunday into Monday.

- A gradual warming trend begins Wednesday with temperatures returning to the low 70s to end the week.

DISCUSSION

Issued at 144 PM CDT Sat Sep 19 2026

The cooler air has arrived across northeastern Nebraska and northwestern Iowa. Current temperatures range from the upper 60s to mid-70s behind the front, with 80s and 90s ahead of it. A shortwave will enter the region later this afternoon and low pressure is currently over Iowa. A cold front will continue to push across the region this afternoon. Ongoing showers continue to march across eastern Nebraska/western Iowa this afternoon, extending from Ceresco to Fort Calhoun and Elk Horn (IA). A few thunderstorms are starting to pop up near the front in an area with some instability. Should any of these storms be able to strengthen, they may produce some gusty winds, hail and heavy rain. Additional chances (20-30%) for showers and a few isolated thunderstorms will linger through the overnight hours.

A disturbance over the Big Horns Sunday morning will progress east across northern Nebraska and the Dakotas through the day, bringing additional chances for some showers and thunderstorms on Sunday and Monday. Expected highs will be very fall-like, topping out in the 50s and 60s. Lows will be a tad chilly, particularly Tuesday morning, dropping into the mid to upper 40s for some and the low 50s for those along and south of I-80.

Weak ridging sets up, moving across the Great Plains and Central High Plains on Tuesday and Wednesday. Expect a break from precipitation chances and the beginning of a gradual warming trend. By Wednesday afternoon, temperatures will return to the mid-60s for many. Thursday highs return to the mid to upper 60s for many, with a few low 70s to our west. Another disturbance enters the region Wednesday night/Thursday, bringing chances for a few showers and thunderstorms.

AVIATION /00Z TAFS THROUGH 00Z MONDAY/

Issued at 622 PM CDT Sat Sep 19 2026

MVFR ceilings are observed at terminals this evening. 2321z radar imagery shows widely scattered showers approaching the KLNK terminal, with arrival expected by 01z. There is some uncertainty on how far east this activity will make it to KOMA, so have left mentions out. Ceilings deteriorate to IFR late this evening, lasting for much of the period before rising to MVFR in the late afternoon. Some model guidance keeps ceilings at LIFR after 10z, but chances for that remain at around 30%. Another arc of showers will affect terminals largely after 17z so have introduced mentions with this issuance. There is a low 10-20% chance for some fog overnight. Winds remain from the north northeast for the duration of the period at 12 kts or less.

OAX WATCHES / WARNINGS / ADVISORIES

NE...None. IA...None.