textproduct: Omaha/Valley

KEY MESSAGES

- Hot and humid weather continues with heat index values in the low 100s across southeast Nebraska and southwest Iowa. A Heat Advisory remains in effect through at least Saturday.

- Oppressive heat will continue into next week along with some small chances (10-30%) for nightly showers and storms. Warm lows in the 70s will provide little relief.

DISCUSSION

Issued at 1132 PM CDT Thu Sep 3 2026

Tonight and Tomorrow:

Water vapor imagery this afternoon features the persistent cutoff low over the Pacific Northwest while broad ridging holds over the eastern two thirds of the CONUS. A few shortwaves continue to spur on convection across northern Minnesota and the Mid-Atlantic, while we continue to see southwesterly flow aloft south of the main surface front draped across the Dakotas towards southern Michigan. Dewpoints have been over-performing over the last two nights, making the late afternoons/early evenings that much more humid, with another warm night in store across the area. Lows across southeast Nebraska into southwest Iowa will struggle to fall below 75 degrees, while the coolest conditions only fall to around 70 degrees. Low-level winds have already ramped up just above the surface, though convergence along the nose of the low- level jet will be pointed well to the northwest, limiting any chances for rain.

Heading into Friday, another hot day is in store as the mid/upper ridge holds over the area with no relief in sight. Afternoon dewpoints in the mid 70s will continue hanging around northeast Nebraska into northern Iowa, while slightly lower values remain to the south where the hottest temperatures are anticipated to be. A continued Heat Advisory will carry forward the message of the dangerous heat -- not just due to the peaks of the heat, but also the duration of the heat heading into the weekend. Heat indices are forecast to top out in the 100-106 degree range, with the worst conditions along and south of Interstate 80.

Saturday and Beyond:

Another warm early morning is expected to be interrupted by convection initiating and being maintained by a nosing low- level jet across eastern South Dakota while additional weaker convection tries to pull itself together across central Nebraska in worse convective ingredients. Once the strength of the LLJ begins waning around sunrise, the weaker convection in central NE should die while the MCS/cluster across South Dakota tries eating into the better instability to its immediate south. As it moves southward (and as time goes on), less and less shear will be available to maintain its strength and the cluster should fade as it pushes into northeast Nebraska and Iowa. Lingering showers and pop-up storms will likely continue along the outflow boundary throughout the afternoon northeast Nebraska and western Iowa, with storm strength expected to be low.

Aside from the shower and storm chances, heat is expected to continue as the main ridge across the area transitions from a center over the eastern half of the CONUS to a position over the western half. Temperatures take a slight dip for Saturday due to the storm activity and resultant clouds, with temperatures expected to rebound into next week. Overall rain chances through the latter part of the forecast continue to remain rather low, owing to the smaller-scale forcing for ascent that will occur, some off the nocturnal jet while others drift in from afternoon convection that initiates along a weak mesoscale boundary. Ensemble models continue to lean towards the hot end of the temperature forecast with us remaining planted on the eastern or western edge of a building ridge heading into next weekend. A "cold" front passage could bring in minor relief towards the middle of the upcoming week, but we'll still be left with above- average temperatures that are still reminiscent of the deep summer while most of the area continues looking forward to fall.

AVIATION /12Z TAFS THROUGH 12Z SATURDAY/

Issued at 520 AM CDT Fri Sep 4 2026

Low-level wind shear is wrapping up leaving mostly 5-10 knot sfc winds forecast over the next 24 hours. Most winds will blow out of the south with some variability in the direction at KOFK and northeast Nebraska.

OAX WATCHES/WARNINGS/ADVISORIES

NE...Heat Advisory until 7 PM CDT Saturday for NEZ044-045-050>053- 065>068-078-088>093. IA...Heat Advisory until 7 PM CDT Saturday for IAZ055-056-069-079- 080-090-091.