733 FXUS63 KOAX 282322 AFDOAX Area Forecast Discussion National Weather Service Omaha/Valley NE 622 PM CDT Sun Jun 28 2026 .KEY MESSAGES... - Dangerous heat is expected today and Monday, with heat index values reaching 105 to 110 degrees in some areas. Overnight minimum heat index values remain in the upper 70s and low 80s. - A few strong to severe storms are possible Monday and Tuesday evening, especially across northeast Nebraska. - Hot and humid weather continues into next week, with occasional evening and overnight storm chances. && .DISCUSSION... Issued at 1210 PM CDT Sun Jun 28 2026 Today and Tonight... Objective analysis this afternoon shows a mid- to upper-level low over the Pacific Northwest, with amplified troughing across much of the western CONUS. Downstream of this feature, strong mid- to upper- level ridging is building into the central Plains and lower Mississippi Valley, with the ridge axis centered near the Mid-South. This is bringing the first day of extreme heat to the area. A warm front has lifted north through the region, and behind it, skies are clearing and temperatures are quickly rising. Temperatures have already reached the upper 80s and lower 90s across much of the area as of 12 PM, climbing around 20 degrees since sunrise. Highs are expected to peak in the mid 90s to around 100 degrees this afternoon. Humidity will add to the uncomfortable conditions as strong southerly low-level flow, including surface wind gusts of 25 to 35 mph, ushers in dewpoints in the 70s. Portions of southwest Iowa may see dewpoints climb into the lower 80s, aided by evapotranspiration. This will push heat index values into the 100 to 110 degree range this afternoon, with the highest values favored across southwest Iowa and the lowest towards the Norfolk and Columbus, Nebraska areas. Little relief is expected overnight, with minimum apparent temperatures only falling into the mid 70s to lower 80s. This will make it difficult for uncooled homes to release the day's heat. With this in mind, an Extreme Heat Warning remains in effect for southwest Iowa and the Omaha metro, with a Heat Advisory in effect farther west. Monday... Temperatures Monday will be very similar to today, with afternoon highs again peaking in the mid to upper 90s and heat index values in the 100 to 110 degree range. The highest values are once again favored across southwest Iowa, where dewpoints will be higher. Lower heat index values, potentially dipping into the upper 90s, are expected across northeast Nebraska where dewpoints remain lower. Southerly winds gusts of 25 to 35 mph will continue. Given this, the Heat Advisory will be allowed to expire for portions of northeast Nebraska, while the remaining Extreme Heat Warning and Heat Advisory continue into Tuesday. On Monday, a mid-level jet steak and compact shortwave disturbance will round the base of the aforementioned trough, which will be centered near the Intermountain West, and eject into the northern Plains. This feature will drape a cold front from an associated surface low in Minnesota southwestward into east-central Nebraska towards a secondary surface low. However, this front will have little impact on temperatures. Instead, it will bring our next chance for precipitation and perhaps a few strong to severe storms, though some uncertainty remains with storm timing. Ahead of the front, a very unstable air mass is expected to develop, with MUCAPE exceeding 4000 J/kg. Shear and forcing for ascent will be the limiting factors, especially early in the period. There is a conditional potential for storms to develop along the front during the afternoon or early evening. If this occurs, storms could initially become surface-based supercells capable of all severe hazards before quickly growing upscale. However, forcing for ascent will be on the weaker side until later in the evening, when the LLJ strengthens and stronger mid-level flow improves shear profiles. This would favor more of an upscale convective cluster and damaging wind threat (DCAPE > 1500 J/kg), especially across northeast Nebraska. Latest CAM guidance has increased confidence that convection will occur, but solutions remain split on when initiation takes place. PoPs currently peak in the 30-60% range. Tuesday and Beyond... By Tuesday, the aforementioned jet streak moving into the northern Plains will help nudge the ridge slightly eastward, leaving the area along the northwestern periphery of the ridge. As a result, temperatures will ease slightly, with highs in the lower to mid 90s Tuesday through Thursday and dewpoints generally in the lower 60s and lower 70s. This will keep heat index values in the 95 to 105 degree range, with the highest values once again favored across southwest Iowa. Daily evening and overnight storm chances continue through at least Thursday as the nocturnal LLJ feeds moisture and elevated instability into the region along the edge of the ridge. Strong to severe storms will again be possible Tuesday afternoon and evening as a shortwave trough pivots from the Front Range into the northern Plains. Another very unstable air mass will be in place, with better forcing for ascent and more favorable shear profiles expected across northeast Nebraska. PoPs of 30-55% are in place. GEFS and EPS- EPS-AIFS based machine learning guidance continue to indicate a 5- 15% probability of severe weather each day through at least Wednesday. Details will likely hinge on smaller-scale shortwave tracks and mesoscale features. Any convection could locally temper the heat through cloud cover and outflow, bringing lower confidence in daily high temperatures in this range, but the broader hot and humid pattern is expected to persist. Hot and humid conditions are expected to hang around into the holiday weekend, with a slight reinvigoration Friday and Saturday as the mid-level height rises slide back westward into the region. This may push highs back in the upper 90s, with a few locations potentially touching 100 degrees. Heat index are expected to reach the 100 to 110 degree range. However, a shortwave disturbance pushing into the northern Plains Saturday may bring another day of thunderstorms chances, and a cold front sweeping through to temporarily drop Sunday highs back into the upper 80s to low 90s. We will have to monitor how the shortwave trends as it approaches. The overall ridge and hot pattern does not look to break down anytime soon, as CPC 6-10 day and 8-14 day outlooks continue to favor above-average temperatures across the region. && .AVIATION /00Z TAFS THROUGH 00Z TUESDAY/... Issued at 618 PM CDT Sun Jun 28 2026 Breezy southerly winds are expected to linger through the night, with LLWS developing overnight. At FL018, southerly winds will be blowing out of the south at about 50 knots with sfc winds closer to 15 knots. Otherwise, expect mostly clear skies to linger over the next 18 hours before partly cloudy skies develop on Monday afternoon. && .OAX WATCHES/WARNINGS/ADVISORIES... NE...Heat Advisory until 9 PM CDT Tuesday for NEZ015-034-044-045- 050-051-065>068-078-088>093. Extreme Heat Warning until 9 PM CDT Tuesday for NEZ052-053. Heat Advisory until 9 PM CDT this evening for NEZ011-012. IA...Heat Advisory until 9 PM CDT Tuesday for IAZ043-055. Extreme Heat Warning until 9 PM CDT Tuesday for IAZ056-069-079- 080-090-091. && $$ DISCUSSION...Wood AVIATION...Nicolaisen