textproduct: Omaha/Valley

KEY MESSAGES

- There is a 20% chance of drizzle Tuesday morning and a few showers in the afternoon and evening, but expect much more dry time than wet.

- Much of Wednesday is favored to be dry before persistent shower and storm chances return Wednesday night and last through Saturday.

- Cool weather will stick around with the rain chances, with a brief warmup and dry period favored on Sunday. Rain chances return early next week.

DISCUSSION

Issued at 1146 PM CDT Mon Sep 21 2026

An upper level low continued to spin along the MN/IA border this evening, with a shortwave very evident in water vapor imagery edging southeast through western SD. Clouds and low level moisture will linger in much of the area overnight into Tuesday and as the aforementioned shortwave pushes in early Tuesday morning, could see a little drizzle develop (20% chance). A few spotty showers will also be possible in the afternoon/evening as some additional shortwave energy currently over UT moves through. In general, though, expect more dry time than wet on Tuesday with temperatures holding in the 60s.

Heading into Wednesday, southeasterly surface flow will ramp up with warm air advection helping to lead to showers and perhaps a few storms, mostly to the west of the forecast area, but a few could sneak in during the day. Despite the southerly flow, temperatures aren't expected to warm all that much, with cloud cover still lingering. If you manage to stay dry on Wednesday, that'll be the day you'll want to mow the lawn, because by Wednesday night into Thursday, we'll see a steady stream of shortwave energy coming out of the Desert Southwest combined with persistent warm air advection and moisture transport pointing into the area. As a result, we'll see rain chances largely remaining above 30-40% through Saturday, generally peaking in the 70-90% range during the overnight and morning hours each day. With very little instability, not expecting much in the way of thunderstorms, but there could be a rumble of thunder every now and then.

Sunday is trending toward a dry and warmer day as an upper level ridge axis quickly slides through and temperatures get into the mid 70s to around 80. However, the dry period looks short-lived with guidance in good agreement that a surface boundary slides through sometime Monday or Tuesday and gives us additional widespread rain.

AVIATION /06Z TAFS THROUGH 06Z WEDNESDAY/

Issued at 1214 AM CDT Tue Sep 22 2026

MVFR to IFR ceilings are in place this evening with winds out of the northeast at around 5 kts or less to make for another tricky TAF forecast, with short-term models being a bit more pessimistic compared to some of the recent obs. With that in mind, the forecast was nudged a bit in that direction, with areas of drizzle expected to develop around 10-14z this morning alongside winds that become increasingly easterly through the day. KOMA and KLNK will trend towards MVFR ceilings after an IFR morning that sees clouds lower once again towards the end of the TAF period headed into tomorrow night.

OAX WATCHES/WARNINGS/ADVISORIES

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