525 FXUS63 KOAX 090433 AFDOAX Area Forecast Discussion National Weather Service Omaha/Valley NE 1133 PM CDT Tue Jul 8 2025 .KEY MESSAGES... - Quiet conditions expected for today with highs in the mid to upper 80s with light and variable winds. - Showers and storms (15-30% chance) develop early Wednesday morning primarily across our west. May see redevelopment again Wednesday evening into Thursday morning (20-40% chance) and some of these storms may be strong to severe. - Higher chances (50-70%) for showers and storms exist Thursday evening into early Friday morning. Some storms may be strong to severe. && .DISCUSSION... Issued at 251 PM CDT Tue Jul 8 2025 .SHORT TERM.../Today through Wednesday Night/ Lingering clouds from the MCS overnight have cleared the forecast area with the H5 shortwave pushing off to the southeast. 19z H5 RAP objective analysis shows the trof and vort max along eastern Iowa into northern Missouri, while a stronger trof across Ontario into Minnesota keeps pushing east resulting in northwest flow aloft. At the sfc, a channel of high pressure extends from southern Manitoba into the Dakotas, eastern Nebraska, and much of western Iowa. Conditions should remain quiet for today with the sfc high pressure dominating much of the Northern Plains. A few CAMs try to generate weak scattered showers this afternoon, but current thinking is that we should remain dry. Highs today will be in the mid to upper 80s with light and variable winds. With continued dew points in the upper 60s to low 70s this afternoon, will still feel uncomfortable outside. H5 mid level high based across the southwest US will result in a few shortwave trof disturbances moving within the northwesterly flow for Nebraska and western Iowa. The first will sneak through later tonight into the early morning hours Wednesday, primarily affecting eastern Nebraska. Forcing in the midlevels remains rather weak, but low level forcing aided by H8 warm air advection may help trigger a few scattered showers and storms. CAMs show convection developing by 10z across far northwestern portions of the CWA, eventually spreading along our western border with the Hastings WFO through about the noon hour Wednesday. Have introduce 15 to 30% PoPs along our western border to account for this. BUFKIT soundings show around 1,000 J/kg of MUCAPE with the instability profile looking skinny. 0- 6 km bulk shear also remains marginal at around 20-25 kts, so not really expecting much regarding severe potential with this activity. Lows tonight will be in the mid 60s with light and variable winds. Another shortwave disturbance will advance from the western Dakotas and Nebraska Panhandle region to the east throughout the day Wednesday. Low and mid level forcing looks a little bit stronger with this wave, but the best instability (around 3,000 J/kg of MLCAPE) and stronger bulk shear are located along our western border into central Nebraska. CAMs show convection firing off across central Nebraska Wednesday afternoon and evening, although differences exist with how the convection tracks east in the evening and overnight hours toward OAX. Some CAMs like the HRRR and HiRes ARW show convection spilling into western portions of the forecast area Wednesday evening where some severe threat may exist as shear is a bit better here. However, forecast soundings show much of the instability across eastern Nebraska remaining capped, so any development will most likely be rooted aloft if convection can spread farther east. Questions also remain regarding how truly unstable the airmass will be given morning convection may hinder atmospheric recovery. The SPC has highlighted primarily western portions of our forecast area in a marginal risk of severe weather, with the main threats being large hail and strong wind gusts. Have kept latest NBM solution where PoPs peak at 20 to 40% across much of the forecast area late Wednesday into early Thursday. Otherwise, highs Wednesday will be in the upper 80s to low 90s with southerly winds around 10-15 mph. Lows Wednesday night will be in the mid 60s to low 70s. .LONG TERM.../Thursday through Monday/ By Thursday, the H5 high across the southwest US will weaken as two shortwave trofs begin developing across the Rockies. These waves will eject to the east into the Dakotas and Nebraska towards midday, eventually fusing together into one main shortwave. Ahead of the approaching wave, will see strong 1000-850 mb moisture transport resulting in low 70s dew points making for a rather unpleasant airmass. This may result in a few spots having heat indices reach the upper 90s to near 100F briefly in the afternoon. With ample instability pooling ahead of the wave, 0-6 km bulk shear of 30 to 40 kts, and large scale forcing for ascent overspreading the area in the afternoon and evening hours, could certainly see strong to severe storms. The SPC has highlighted the entirety of our service area in a slight risk of severe weather for Thursday, with all modes of severe weather possible at initial onset before upscale growth. Will also need to keep an eye on the potential for heavy rainfall. Given the ample low level moisture, PWAT values range from 1.75 to 2 inches, and coupled with warm cloud depths of 4,000 meters, expect to see efficient warm rain processes. Some portions of northeast Nebraska and west central Iowa could see up to an inch and a half of rain by early Friday morning. This has prompted the WPC to issue a slight risk for excessive rainfall across much of eastern Nebraska and western Iowa for Thursday. PoPs currently peak Thursday evening into early Friday morning at 50 to 70%, gradually moving east overnight. PoPs linger on Friday as the shortwave will stick around for one more day before pushing out Friday evening (30-60%, with highest chances in western Iowa). A low end chance (15%) for a shower or storm exists south of I-80 on Saturday as a weak shortwave sneaks through northwesterly flow aloft, but best chances remain well south into Kansas. Sunday through Monday will see low end chances (15-20%) for scattered showers and storms as northwesterly to nearly zonal flow at H5 allows a few shortwaves to move through the forecast area. Aside from Friday and Saturday where temperatures cool to the upper 70s and low 80s, highs in the extended will remain in the mid 80s to low 90s. && .AVIATION /06Z TAFS THROUGH 06Z THURSDAY/... Issued at 1133 PM CDT Tue Jul 8 2025 VFR conditions this evening with winds out of the southeast. We`ll have a 30% chance of storms developing northwest of KOFK early Wednesday around 10-13Z and progressing southeastward. Confidence is too low at this point to include in the TAFs. Feeling more than likely we see only an isolated storm or two if any. Winds will remain out of the south or southeast through tonight with VFR conditions holding through the end of the TAF period. && .OAX WATCHES/WARNINGS/ADVISORIES... NE...None. IA...None. && $$ DISCUSSION...Castillo AVIATION...McCoy