FXUS63 KOAX 051841 AFDOAX Area Forecast Discussion National Weather Service Omaha/Valley NE 141 PM CDT Wed Aug 5 2026 .KEY MESSAGES... - Clearing conditions become more widespread to cap off a splendid day, with fog development overnight likely. - Milder temperatures through Thursday warming back up going into the weekend. Seasonably warm weather expected over the weekend. - Chances are increasing for a few strong to severe thunderstorms Saturday afternoon and evening. - Wildfire smoke continues to drift in from the north, with only small amount reaching the surface. && .DISCUSSION... Issued at 128 PM CDT Wed Aug 5 2026 Today and Tonight: Water vapor imagery this afternoon continues to feature broad troughing centered over the central third of the CONUS, with a shortwave embedded at the base sweeping shower and storm activity farther to the east into Missouri and Iowa. Drilling down to the surface, we find ourselves in a post-frontal airmass with the front itself draped across the Southern Plains into the mid- Mississippi Valley/Great Lakes region. Elevated shower and storm activity is slated to continue across far southeast Nebraska into Iowa for the next few hours before being further shunted off to the east, with easterly winds taking over at 5-10 mph. Temperatures in the mid 70s to just over 80 degrees are set to cap off an excellent afternoon with increasingly clear skies -- setting the stage for fog chances overnight. Winds are set to decrease underneath the building nocturnal inversion overnight, as a ridge of high surface pressure helps calm conditions across the area. HREF model output signals very little insulating cloud cover aside from some low stratus across far southeast Nebraska and Iowa, fog development likely where healthy rainfall occurred this morning. Crossover temperatures are only 3-4 degrees above the overnight low, giving some uncertainty to the density and southern extent of the fog. Some models do limit its formation into Nebraska, favoring southern Iowa and points northeast, from 4 AM to 9 AM tomorrow morning. Thursday and Beyond: Once winds begin to pick up Thursday morning and become more steady out of the southeast, lingering areas of fog should clear up and leave us with a slightly warmer, but still pleasant day that tops out in the 80s. Shower and storm chances should remain across northeast Kansas and to the northwest along a surface trough draped across north-central Nebraska into South Dakota. Friday into the weekend, we'll be plowing into a warming trend spurred on by mid-level height rises, a retreating jet stream, and building thermal ridging just to the west of the area. One hangup with the weekend forecast is just how much we will warm. The mix- happy GFS/GEFS will steer the forecast towards highs that reach well into the 100s while the rest of the global ensemble members have a much more tentative lean that sets highs in the upper 80s to lower 90s (which is where our forecast sits as well). Surface data from the global models have a lingering boundary/front that sits across or near the forecast area, and serve as a focus for cloud/precipitation development that could affect the highs. A modest overlapping of ingredients for severe storms stretches each day from Friday through much of next week, peaking Saturday. Confidence isn't there quite yet to pin any locations down on a map, but don't be surprised if something shows up for tomorrow's issuance of the Day 3 Severe Outlook from the SPC. && .AVIATION /18Z TAFS THROUGH 18Z THURSDAY/... Issued at 1218 PM CDT Wed Aug 5 2026 Pesky IFR ceilings have been hanging around at KOMA/KLNK a bit longer than initially anticipated, with those expected to lift over the next hour in favor of MVFR ceilings that scatter out shortly thereafter. Aside from the low clouds, another layer sits well above them with some low-end chances for rain (15%) at KLNK through 20z. Winds will remain light into the evening with growing confidence in fog development at KOMA/KLNK with the latest timing in the TAFs. If confidence continues to increase, expect to see worse conditions (IFR or worse) incorporated in future issuances. && .OAX WATCHES/WARNINGS/ADVISORIES... NE...None. IA...None. && $$ DISCUSSION...Petersen AVIATION...Petersen