815 FXUS63 KOAX 271047 AFDOAX Area Forecast Discussion National Weather Service Omaha/Valley NE 547 AM CDT Sun Jul 27 2025 .KEY MESSAGES... - A renewed stretch of dangerous heat is forecast for this afternoon and again on Monday - potentially stretching into Tuesday. Afternoon heat index values may reach 105 to 115 degrees. - Drier conditions are favored through at least mid-day Monday, with higher storm potential returning late Tuesday into Wednesday. Some of these storms could be strong to severe with damaging winds and localized flooding the main threats. - Cooler conditions return for next week`s second half with on and off rain chances. && .DISCUSSION... Issued at 500 AM CDT Sun Jul 27 2025 For a third consecutive morning, patchy fog has developed with most obs reporting calm winds. Again, fog has been noted first in southwest Iowa and along the Missouri River. Tonight`s winds at H9 are a little stronger so fog expansion may be more difficult than past nights. Guidance keeps the fog limited mostly to Iowa and far eastern Nebraska. IR satellite shows the anvil of some convection building into northeast Nebraska as the storms in the central part of the state weaken. They`re trying to build into a more stable environment. We expect this forecast area to remain dry through at least Monday night. WV imagery shows nearly zonal flow along the Canadian border with a H5 ridge centered over Atlanta. That ridge will experience retrograde expansion over the next 48 hours as heights climb over the central CONUS. Much of the country is anticipating some of the year`s hottest temps. Today`s highs will be 4-10 degrees higher than Saturday thanks to stronger southerly winds and widespread sunshine. There may be a little early morning haze hanging over northeast Nebraska / northern Iowa early this morning. This is wildfire smoke from northern Arizona. Skies should turn bluer quickly and remain that way for the remainder of the day. Highs level off in the mid-90s this afternoon with dewpoints reaching sticky mid-70s. The resultant heat indices justify an EXTREME HEAT WARNING (near 110F) for most of the CWA with Saline, Jefferson, Gage, Pawnee, and Shelby counties under a HEAT ADVISORY (near 105F). A heat index of 110F is recorded at Eppley at just over half of summers. Most summers do NOT hit 111F there. Consideration was also given to the fact that uncooled homes won`t see much relief overnight as temps slip only into the mid-70s for many. It`ll be all the worse for those in the heart of an urban heat island. The heat will ramp up just as high or higher again on Monday. For this reason, the headlines will remain in place overnight. BTW: We are in the middle of average peak "corn sweat" season when evapotranspiration of corn typically peaks (July 20-August 10 last year). When conditions are correct, this can push dewpoints higher and prevent temperatures from hitting expected peaks. .MONDAY... With the launching pad of mid-70s, temps should zip through the 80s and approach the century mark by Monday afternoon. It`s been a month since that`s happened. Most cities will fall shy, but heat indices will look like Sundays plus a degree or two. 95 degrees and a 55 degree dewpoint is one thing, but this heat/humidity combo is just plain dangerous. Make plans now to keep cool. Some severe weather potential exists for Monday night, but plenty of questions remain. A ring-of-fire type of storm is expected to initiate on the northern edge of the building ridge. The storm complex is most likely to develop in central South Dakota just south of the cold front and trend toward southern MN / northern IA overnight. Some thunderstorm activity could (20%) clip our northernmost counties in this scenario, mostly in the evening hours as upscale growth into an MCS produces a wind threat. The rest of the area would remain dry. .TUESDAY... Considered adding heat headlines for Tuesday, but much uncertainty still exists. We`re currently calling for temperatures in the upper 80s to mid-90s and advisory criteria heat indices along and south of I-80. Much depends on the final location and timing of the front that will be settling into the CWA. Outflow boundaries from Monday night`s convection could throw a wrench into the convective forecast, too. As it stands, shear and instability look robust. SPC has highlighted the area and machine learning processes agree. An MCS could develop along the front and PoPs peak after midnight (40-70%) thanks to the LLJ. .THE REST OF THE FORECAST... Cooler air builds in from the north as an H5 trof develops over the Great lakes. After dangerous heat brings an end to July, days five, six, and seven of the forecast - the first three of August - will have to tolerate highs falling well shy of seasonal norms with Tuesday`s cold front now well south of the Corn Belt. && .AVIATION /12Z TAFS THROUGH 12Z MONDAY/... Issued at 545 AM CDT Sun Jul 27 2025 Skies will remain mostly clear through the TAF period and VFR conditions are forecast. Southerly winds will become quicker this afternoon with some gusts of up to 20 knots. Later tonight, low level wind shear is expected to develop as surface winds calm and stronger winds continue just off the surface from the southwest. && .OAX WATCHES/WARNINGS/ADVISORIES... NE...Extreme Heat Warning from noon today to 8 PM CDT Monday for NEZ011-012-015>018-030>034-042>045-050>053-065>068-090- 091-093. Heat Advisory from noon today to noon CDT Monday for NEZ078- 088-089-092. Extreme Heat Warning from noon to 8 PM CDT Monday for NEZ078- 088-089-092. IA...Extreme Heat Warning from noon today to 8 PM CDT Monday for IAZ043-055-069-079-080-090-091. Heat Advisory from noon today to noon CDT Monday for IAZ056. Extreme Heat Warning from noon to 8 PM CDT Monday for IAZ056. && $$ DISCUSSION...Nicolaisen AVIATION...Nicolaisen