314 FXUS63 KOAX 050637 AFDOAX Area Forecast Discussion National Weather Service Omaha/Valley NE 137 AM CDT Sat Jul 5 2025 .KEY MESSAGES... - Scattered showers and thunderstorms will gradually diminish through the morning hours. - Storm chances return this afternoon across southeast NE and southwest IA, with a 5-10% chance of producing quarter-sized hail and wind gusts up to 60 mph. - Daily storm chances (20-30%) continue from Sunday night through the work week. While the severe threat remains low, repeated rounds of rainfall may lead to localized flooding concerns. && .DISCUSSION... Issued at 135 AM CDT Sat Jul 5 2025 Today and Tonight... Upper-level analysis this morning reveals a mid- to upper-level ridge anchored over the southeastern CONUS, with broad troughing over the western CONUS and a deamplifying shortwave lifting northeast across the northern Plains. At the surface, a trough associated with this passing disturbance is sweeping across eastern NE, supporting scattered to widespread thunderstorms. As of 1 AM, KOAX radar indicates a band of reflectivity extending from northeast NE into central NE as convection redevelops with a final vorticity maximum sweeping across the area. The severe weather threat with this activity remains limited, given modest bulk shear (20-25 kts) and weak instability (MLCAPE < 1000 J/kg). A few stronger wind gusts (30-40 mph) may accompany any decaying storms, but the threat appears low. Locally heavy rainfall will remain a possibility with these early morning storms as PWAT values linger in the 1.75-2.00" range (above the 90th percentile of OAX sounding climatology) and model soundings indicate 3-4 km of warm cloud depth along with long, skinny CAPE profiles. This is especially the case in northeast NE where a near stationary band of northeast progressing storms is setting up. This early morning convection will gradually shift east and dissipate by mid to late morning, with most of the area clearing out by 9-11 AM. Cloud cover will decrease through the day, allowing afternoon highs to climb into the 80s to low 90s. In the wake of the departing system, a surface low will hinder over the MI/WI region, trailing a cold front southwestward into eastern NE and southwest IA by mid-afternoon. Scattered thunderstorms are expected to develop along this boundary, tracking southward into the evening. A few strong to severe storms will be possible, supported by moderate MLCAPE values (1250-1750 J/Kg) and steep mid-level lapse rates. While bulk shear will remain relatively weak (20-25 kts), it should be sufficient for some initial storm organization before cold pools eventually become unbalanced. The primary hazards will be damaging wind gusts (up to 60 mph), aided by modest DCAPE values (1000-1250 J/kg), with isolated instances of hail up to 1" possible with any stronger updrafts. Storms are expected to weaken and exit the area by midnight. The SPC has outlined southeast NE and southwest IA in a marginal risk (level 1 of 5) for severe weather. Sunday and Beyond... A mid-level ridge will briefly slide over the area on Sunday, bringing a temporary break from precipitation and allowing highs to climb into the 80s. Seasonable conditions are expected to continue through the work week, with daytime highs generally in the 80s to low 90s and overnight lows in the upper 60s. By early next week, the large-scale pattern will shift to feature troughing over the south-central CONUS, with broadly zonal to northwesterly flow aloft across the region. This setup will support a series of weak disturbances tracking through the area throughout the week. The aforementioned cold front is expected to stall and transition into a stationary boundary, meandering north and south through the area and acting as a focus for periodic showers and thunderstorms, further aided by passing shortwave disturbances. Precipitation chances (PoPs 20-30%) return late Sunday night into Monday as the first in a series of disturbances slides across the northern Plains. PoPs will continue in the 20-30% range for much of the work week. However, confidence remains low in the timing and placement of individual disturbances and their associated precipitation. While no day stands out as a clear threat for severe weather, isolated strong to severe storms can`t be ruled out. GEFS and ECMWF ensemble-based machine learning guidance currently highlights a 5-10% probability for severe weather across the region during this period. The primary concern will likely shift towards localized flooding, with repeated rounds of heavy rainfall possible through the week. && .AVIATION /06Z TAFS THROUGH 06Z SUNDAY/... Issued at 1128 PM CDT Fri Jul 4 2025 The southern portion of the line of storms has fizzled away leaving behind a broken line of showers that may move into KLNK around 06Z. Otherwise, storm chances wane until the next round arrives around 08-09Z where we may see storms redevelop along the original boundary right over KOMA as well as a second line move into northeast Nebraska. We`ll see these storms move through, exiting the area around 12Z with winds turning more southwesterly. Once storms exit, attention turns to low stratus expected to develop over northwest Iowa and expand southward into KOMA. Some models bring this west as well, into KLNK and KOFK, but highest confidence is in it impacting KOMA around 13-16Z Saturday morning. This should erode by 16Z with clearing skies for the afternoon. We have additional low chances for storms Saturday afternoon (15-30%), but chance is too low to include in the TAFs for now. More likely sites stay clear. Winds will shift to west then northwesterly by Saturday afternoon, staying out of the northwest through the remainder of the TAF period. && .OAX WATCHES/WARNINGS/ADVISORIES... NE...None. IA...None. && $$ DISCUSSION...Wood AVIATION...McCoy