Area Forecast Discussion
Issued by NWS Omaha/Valley, NE
Issued by NWS Omaha/Valley, NE
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116 FXUS63 KOAX 142326 AFDOAX Area Forecast Discussion National Weather Service Omaha/Valley NE 626 PM CDT Tue May 14 2024 .KEY MESSAGES... - Precipitation chances increase tonight through Wednesday night. A Marginal risk of severe weather is present Wednesday afternoon into the evening. - Smoke/haze remains in the area today, causing moderate air quality. - -Spotty precipitation chances are present Friday through Monday but confidence remains low, this period probably remains drier than wet. && .DISCUSSION... Issued at 306 PM CDT Tue May 14 2024 Short Range (Today through Thursday) Despite moderate air quality from Canadian wildfire smoke making its way into the area, clear skies are present across the region this afternoon. This is thanks to a ridge axis over the area as we sit between a departing low pressure system to the southeast and an incoming disturbance to the west. As a result, we are presented with north-northwesterly flow aloft. High temperatures are peaking in the mid to upper 70s across the area. A shortwave trough traversing across western NE/SD has spun up a weak surface low over northwestern Nebraska this afternoon with an associated weak cold front draped across the western portion of the state. Thunderstorms are expected to initiate along the front over central Nebraska (west of our CWA) this afternoon before weakening and moving east. These thunderstorms have the potential to make their way into our westernmost counties before bringing scattered rain shower potential (30-50% PoPs) to the rest of the area. Overnight showers may linger into the early morning hours on Wednesday before breaking up and bringing high temperatures in the lower 70s. The aforementioned surface low is expected to track into eastern SD by tomorrow afternoon with the associated weak cold front oriented north-south into eastern Nebraska and down into KS/OK. The front is expected to arrive in the CWA Wednesday afternoon with the development of scattered and potentially severe thunderstorms. Buoyancy will be the limiting factor for our severe weather potential as MLCAPE struggles to increase above 500 J/kg. The SPC has placed the southern majority of our CWA in a marginal risk for severe weather including hail up to 1" and wind gusts up to 60 mph with the initial stronger updrafts. The front will continue its route eastward through the area Wednesday night into Thursday morning (PoPs 40-70%). Rainfall totals south of Interstate 80 are expected between 0.25 and 0.75 in. with values decreasing as you progress northward. A couple showers may continue to work their way through the area Thursday morning before cloud cover breaks up during the afternoon. The cold front will have minimal effects on Thursday temperature as highs are expected in the upper 70s. Long Range (Friday through Monday) Zonal flow will return towards the end of the work week. A few week shortwaves traversing the region could bring the potential for light and scattered rain showers Friday into Saturday. High temperatures Friday into the weekend are expected to reach into the upper 70s/80s. Saturday may be the warmest day of the week with high temperatures in the upper 80s. Our next chance at measurable precipitation looks to be Saturday night into Sunday morning as a front sweeps across the area. Model agreement is low on the placement and moisture content of this event so an eye will be kept on it as it approaches. As of now, PoPs remain as a widespread 20-30%. Model variability continues to increase into Monday with the ECMWF bringing widespread showers and thunderstorms and most GEFS ensemble members leave the majority of the area dry. PoPs on Monday remain as a widespread 40% as we await the details to work themselves out. && .AVIATION /00Z TAFS THROUGH 00Z WEDNESDAY/... Issued at 615 PM CDT Tue May 14 2024 Very light southeasterly winds kick off the forecast period with main updates for the 00z TAFs being the inclusion of storms tomorrow afternoon and increasing potential for low ceiling and secondarily visibility around sunrise near KOMA and KLNK. Before that, scattered shower and storm activity in northern Nebraska and south-central South Dakota will continue to develop eastward, weakening by the time it gets to KOFK. Recent runs of the short- term models have been increasing the coverage of lower visibilities from 12-14z, with MVFR to IFR ceilings developing before and lingering afterwards at KOMA and KLNK, with thunderstorms expected to move in during mid- afternoon and leave the area by 00z. && .OAX WATCHES/WARNINGS/ADVISORIES... NE...None. IA...None. && $$ DISCUSSION...Wood AVIATION...Petersen