textproduct: Omaha/Valley

KEY MESSAGES

- A Flood Watch is in effect through Wednesday evening. The flash flood threat is highest for areas that have already received several inches of rain.

- 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 increased 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 /12Z TAFS THROUGH 12Z WEDNESDAY/

Issued at 522 AM CDT Tue Sep 15 2026

Widely scattered showers with embedded thunderstorms continue across the region. Recent development to the west of LNK and OMA has shown lightning, but this is expected to diminish over the next few hours. Showers may still linger into the afternoon. In general, VFR visibility and ceilings are expected, but very brief reductions to MVFR visibility and ceilings may occur. OFK is expected to reside north of this activity. After 18Z, a gradual end to rain occurs from north to south, but there is some uncertainty on how long rain lingers at OMA and LNK. This rain could linger into the mid-afternoon, but all terminals should be dry this evening. Otherwise, north to northeast winds are expected during the period. As another weather system approaches the region tonight, a reduction to ceilings is likely towards the very end of the TAF period.

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.