textproduct: Omaha/Valley

KEY MESSAGES

- There is a slight chance (20%) for isolated showers or storms through early this evening. Any storms may produce heavy rainfall rates up to 2 inches per hour.

- Scattered showers and thunderstorms are expected to move into eastern Nebraska late tonight into Thursday morning. Heavy rainfall will again be possible under the strongest storms.

- A more widespread line of thunderstorms is likely to move across the region later on Thursday into Friday morning. Damage wind will be possible with the initial line of storms, along with heavy rain and small hail.

DISCUSSION

Issued at 1239 PM CDT Wed Jul 29 2026

Current Conditions

The morning convective complex has largely dissipated as of 1 PM with a few lingering showers remaining. The weak, slow-moving short wave trough that helped drive this system is centered over central KS with a slow southeastward progression, and a generally lessening influence this far north. The morning storms developed in a rather moist airmass, with low level moisture feed off the Gulf and a mid/upper level moisture feed around the ridge from the Baja region. This helped the stronger cells to produce 2-3" per hour rainfall rates where they stalled. This atmospheric moisture content is actually expected to increase slightly in the next 36 hours with the approach of a stronger short wave trough out of the CA/NV region. This should bring PWAT of 2-2.2" to parts of the area in advance of the next round of storms. The incoming western short wave trough will dampen the upper ridge and cool temperatures a bit over the next few days, in addition to precip potential.

Through Early Thursday

Some weak smaller-scale forcing will rotate around the ridge tonight with a slight increase in low level jet speed over central KS. This will increase moisture transport into western parts of the forecast area with some LLJ convergence gradually lifting northeast into the forecast area around sunrise or shortly thereafter. This should support another round of scattered showers and thunderstorms with potential for pockets of heavy rain. This area of weak forcing may persist into the early afternoon hours, with the main question being how widespread any convective showers/storms can be. Deep forcing is weak, but capping is very limited and when paired with a deep moist environment it probably won't take much forcing to sustain scattered storms. If convection is more widespread tomorrow, it may limit daytime heating and instability recovery which would lessen the late day severe potential...but fewer storms during the day may warrant a bit more of a damaging wind potential for late Thursday.

Late Thursday into Friday

The main show is expected on Thursday evening as the stronger deep layer forcing pushes east. Expect the cold front entering north central Nebraska to convect along the boundary. This will likely transition quickly into an MCS as numerous updrafts in close proximity conglomerate into a single forward propagating cold pool. The theta-e and MLCAPE axes will extend from that north central NE convection to the southeast while low level shear vectors point east or east southeasterly. This would appear to favor individual outflow surges directed toward the east southeast while the larger MCS outflow system eats toward the southeast into the instability axis. That instability does not extend terribly far east of the Missouri River so the intensity should wane with eastward progression. The wind and instability fields with this system appear to be sufficient to support severe wind in segments, but are not forecast to be impressive enough to support a persistent high-end wind storm across a wide expanse. Additionally, the moisture content suggests that rainfall rates could exceed 2" per hour in heavier cores, so any training elements will need to be monitored for flooding potential. Showers or a storm may linger into Friday, but the trough passes east of the area with subsidence overtaking and drying out the region by late in the day.

Saturday Into Next Week A rather weak northeastward extension of the upper ridge axis from the Four Corners region will keep the local area mainly dry through Monday or so, with surface high pressure slowly drifting overhead and then east of the area. Highs will be largely in the 80s to low 90s with lows in the 60s in a less humid airmass. By late Monday into Tuesday, model guidance is strong in bringing a glancing influence of a strong Canadian trough with a front sagging toward northern parts of the area. This will bring thunderstorm chances if the front makes it this far south.

AVIATION /18Z TAFS THROUGH 18Z THURSDAY/

Issued at 1225 PM CDT Wed Jul 29 2026

While there are some BKN MVFR cigs hanging around OMA at 18Z, believe that it will scatter and lift to VFR by 18Z or very shortly thereafter. Then expect VFR for the remainder of the TAF period. There is some potential for SHRA or TSRA at all sites mainly in the 10-14Z window, but it will be scattered precip so have not included at this time.

OAX WATCHES/WARNINGS/ADVISORIES

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