Area Forecast Discussion

KEY MESSAGES

- A Flood Watch is in effect through Tuesday evening. If additional storms Tuesday night into Wednesday look like they'll impact the same areas, the watch may need to be extended.

- A wet pattern continues through the week with daily shower and storm chances. While the threat for hail, damaging winds, and tornadoes will diminish, repeated rounds of rain may lead to an increasing flooding threat.

DISCUSSION

Issued at 1054 PM CDT Mon Sep 14 2026

Tonight through Tuesday...

A line of storms swept through the region this evening, bringing damaging winds, and a potential tornado near Avoca, NE.

A 50 kt LLJ will nose into the region tonight, bringing a resurgence of showers and storms to the region. Observed PWATs around 2" exceed the 99th percentile, climatologically. Rainfall rates of 2" per hour will be possible with deep warm cloud layers of around 10,000 ft. CAM QPF totals suggest rainfall amounts of 1-3" along and south of a line from Lincoln to Omaha, with higher amounts, up to 3-5" in far southwest Iowa. Areas of flash flooding appear likely through Tuesday morning, as several storms likely train over the same locations. A Flash Flood Watch remains in effect for most of southeast Nebraska and southwest Iowa through Tuesday evening, when the majority of precip finally shifts south of the forecast area.

Wednesday and Beyond...

A steady stream of shortwave energy will continue Wednesday into Thursday while the surface boundary slowly meanders back north, eventually reaching SD by Friday. At least on and off showers and storms will be possible through that period, with potential for repeated rounds of rain to lead to flooding concerns. Friday is generally favored to be a drying period, though still looking at 20- 30 percent chance of rain in the afternoon with a few various ensemble members a little slower with the northward advancement of the front. However, any dry period looks to be short- lived as a cold front pushes in from the northwest for the weekend and gives us continued 30-50% chances of rain. Machine learning severe weather guidance keeps severe weather potential below (under 5%) through this active period, though again, potential heavy rain and flooding will remain a concern with each successive round.

Otherwise, temperatures may be a bit of a roller coaster through the week and will hinge on precipitation on a given day. Currently, upper 60s and 70s are favored Tuesday and Wednesday before the front moves back north and marks a return to the 80s Thursday and Friday. Behind the weekend cold front, expect to be back down in the 70s to lower 80s. But again, lots of moving parts, so confidence in exact temperatures on a given day is relatively low.

AVIATION /06Z TAFS THROUGH 06Z WEDNESDAY/

Issued at 1202 AM CDT Tue Sep 15 2026

Thunderstorm activity has been a bit more widespread than initially forecast this evening, with storms expected to continue through 10 to 12z before becoming increasingly intermittent through tomorrow morning. Models as of now still show shower and storm chances lingering for a few more hours, but if activity continues through much of the overnight, this area should shift south early. Otherwise, northerly winds will become widespread by 08z this evening at KOMA/KOFK before arriving at KLNK at 12z, shifting northeasterly during the afternoon and evening hours. VFR conditions are expected aside from a strong thunderstorm (15% chance) where visibility would be reduced for it's duration into MVFR/IFR territory.

OAX WATCHES / WARNINGS / ADVISORIES

NE...Flood Watch through this evening for NEZ052-053-066>068- 089>093. IA...Flood Watch through this evening for IAZ069-079-080-090-091.