textproduct: Omaha/Valley

KEY MESSAGES

- Patchy fog is expected tonight into Monday morning.

- Widespread shower and thunderstorm chances (90%+) return Tuesday morning through Thursday. - Forecast rainfall totals of 2-4+ inches may bring a flooding concern to area rivers and streams.

DISCUSSION

Issued at 1111 PM CDT Sun Sep 27 2026

It was a beautiful Sunday for many with sunshine returning by the late afternoon and evening. Unfortunately this will be short-lived as low clouds and patchy fog redevelop tonight. Low clouds and fog are expected to linger into the late morning and early afternoon, but a few breaks in the clouds may again be possible by the late afternoon and evening on Monday. Outside of a damp morning, the weather will remain dry with highs in the 70s.

The dry weather comes to a swift end Tuesday morning. A large upper-level trough near the Four Corners begins to ingest rich tropical moisture from the remnants of Polo. As this occurs, an area of surface low pressure develops ahead of these features over the south-central Plains before lifting northeast towards our region on Wednesday. The upper-level trough does not move over the area until Thursday afternoon. A cold front will then push through the region, sending rain south, and bringing and end to the rainfall. Widespread showers and thunderstorms (90%+ chance) are anticipated through this time frame. With significant rainfall totals likely for the region. Temperatures will remain in the 60s to low 70s each day due to continued rain and cloud cover.

Diving into the details of this rainfall, some uncertainty remains, but confidence is increasing in widespread rainfall totals of 2-4"+ for the area. These rainfall totals will be fueled by a warm, moist airmass more typical of the gulf coast rather than Fall in the Plains. Despite limited instability, warm rain processes will favor high rainfall rates in any showers and thunderstorms that develop. That said, the exact track of the area of low pressure and the coinciding region of greatest rainfall continues to shift slightly with the latest forecasts. In either case, a flash flood threat may develop if a corridor of repeated heavy rainfall develops. One mitigating factor to this scenario is the duration and placement of heaviest rainfall may be short-lived minimizing rainfall totals for any particular area. With that being said, the ceiling for this event remains high and rainfall amounts could come in higher than anticipated in a higher-end scenario. This will be closely monitored as confidence increases with convective models coming into range for this event. While the flash flood threat remains more conditional, river flooding is a more likely hazard. Area rivers and streams have already seen rises due to recent rainfall and may be primed for flooding with this next event. If you are located in a flood plain, monitor your river forecast closely as flooding may become a concern next week.

Once this system clears the area on Thursday, a cooler and drier Fall airmass fills in across the Plains. Even though we expect sunshine to return to the area behind this system, cool temperatures linger into next weekend. We can expect highs in the 60s with lows in the low 50s to upper 40s. These temperatures would be some of the coolest since late Spring. While significant, these temperatures are too warm for any frost potential and a delayed first frost compared to average continues for the area.

AVIATION /06Z TAFS THROUGH 06Z TUESDAY/

Issued at 1222 AM CDT Mon Sep 28 2026

A band of MVFR/IFR stratus is observed over most of KOFK and KOMA with ceilings around 900 to 2,000 ft. Should see more stratus develop and enter the KLNK vicinity in the next few hours. Ceilings then deteriorate to IFR after 08z. Have delayed the arrival of IFR ceilings at KOFK and KLNK by a few hours based on latest model guidance. KOFK will see the worst of the impacts, and even some LIFR ceilings. There is some potential for fog at terminals early this morning resulting in MVFR visibilities. Visibilities improve after 14z, while ceilings don't lift to MVFR until the afternoon. VFR prevails closer to 00z with clouds at around 4,000 ft. Winds remain under 12 kts for the duration of the cycle and from the east southeast.

OAX WATCHES/WARNINGS/ADVISORIES

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