A strong ridge of high pressure stretched from Arizona into the northern Rockies. Air sinking beneath the ridge compressed and warmed, trapping intense heat close to the ground under mostly clear skies. Meteorologists expected the episode to be relatively short-lived, but it arrived over landscapes already dried by earlier heat, low humidity and active wildfires.
Las Vegas reaches 115°F
Las Vegas climbed to 115°F (46°C), its hottest temperature of 2026 and only 1°F below the daily record of 116°F (47°C). The temperature was around 10°F above normal, while another high near 114°F (46°C) was expected Sunday.
The August record for Las Vegas is 116°F (47°C). The city’s all-time high of 120°F (49°C) was set in July 2024, during its hottest summer on record. National Weather Service forecasts also placed daily maximum and overnight minimum records at risk during the heat wave.
Phoenix was forecast to reach 116°F (47°C), while El Centro, California, could hit a record 118°F (48°C). Farther north, Great Falls, Montana, was forecast to reach 104°F (40°C), while Helena could approach its daily record of 102°F (39°C).
HEAT WAVE
— Sid (@Trending_Sid) August 2, 2026
🌊 Heat, wind, drought fuel dangerous flames in US
More than 50 million Americans from California to Montana are under heat alerts.
East Las Vegas Residents Struggle Amid Extreme Heat Wave#Oregon #LasVegas #Montana #WildFires #NarcoRégimen #HeatWave #WeatherAlert pic.twitter.com/I600HFv9ox
Much of eastern Montana was placed under an extreme heat warning, although a sharp cooldown was expected by Sunday. The latest heat was less severe than the mid-July event, when Billings reached an all-time record of 111°F (44°C).
The danger continued after sunset. Overnight lows across parts of southern Nevada, southeastern California and Arizona were expected to remain in the upper 80s to lower 90s Fahrenheit, around 31°C to 34°C.
Warm nights prevent buildings and human bodies from releasing the heat accumulated during the day. Repeated exposure without an overnight recovery period raises the risk of heat exhaustion and heat stroke, especially for older adults, outdoor workers and people without reliable air conditioning.
Cooling centers remained open in affected cities, while residents were urged to limit strenuous outdoor activity, drink water regularly and check on vulnerable neighbors.
The heat dome also accelerated moisture loss from grass, shrubs and forest fuels. Afternoon relative humidity dropped into the single digits across parts of Nevada, making vegetation easier to ignite and allowing existing fires to burn more intensely.
Most of Montana was under red flag warnings as high temperatures overlapped with dry fuels and strong winds. Enhanced wildfire risk also covered most of Southern California away from the immediate coastline.
Heat alone does not produce the fastest-moving fires. The most dangerous conditions occur when extreme temperatures and very low humidity combine with strong or erratic winds. These winds can push flames rapidly through dry vegetation and carry embers across roads, rivers and containment lines.
Extreme fire weather grips Washington & Oregon
Washington declared a state of emergency as unusually high temperatures and powerful winds intensified an already severe fire season. Most outdoor and agricultural burning was also prohibited through the end of September.
The National Weather Service issued a rare “particularly dangerous situation” red flag warning for eastern Washington, indicating an extreme risk of rapid fire growth.
WATCH: Buildings engulfed in flames as the Old Trails Fire sweeps through Spokane County, Washington. Over 3,000 acres have burned, with more than 5,000 homes under threat. pic.twitter.com/7faiIHmI2p
— Scope Report (@ScopeReport_) August 2, 2026
Near Spokane, the Old Trails Fire raced through dry grass and brush, crossed the Spokane River and forced thousands of people to evacuate. The fast-moving fire was driven by strong winds and high temperatures as it approached residential areas.
Devastation in 📍 Spokane, Washington.
— PNW Conservative (@PNWConservative) August 2, 2026
Pray for the impacted and pray for our men and women courageously fighting the fires. pic.twitter.com/A1sEi2FLJg
Critical fire weather also extended into eastern Oregon, where crews continued battling several large fires.
The Rowe Creek Complex had grown to around 490 square miles (1,269 square kilometers), with containment reported at 57%. Hot temperatures, very low humidity and gusty winds continued to challenge crews and increase the risk of renewed fire growth.
A rotating column of flames, smoke and embers, commonly described as a “firenado,” was also observed over the burning area. These intense vortices are usually fire whirls, created when extreme heat produces rapidly rising air and nearby winds tighten the airflow into rotation.
Fire whirls (firenadoes) can lift burning debris high above the ground and scatter embers beyond the main fire front, potentially creating new outbreaks and making conditions even more unpredictable. True fire-generated tornadoes are much rarer and require a stronger, more organized rotating circulation.ent.
Firenado in Harney County, Oregon. pic.twitter.com/DXRSJHYLCZ
— Massimo (@Rainmaker1973) August 2, 2026
The ridge was expected to weaken relatively quickly, allowing temperatures to fall across parts of the northern Rockies. However, a brief cooldown will not immediately restore moisture to vegetation, soils or larger forest fuels.
Human-caused climate change is increasing the likelihood of more frequent, intense and longer-lasting heat waves. In the West, hotter conditions and a drier atmosphere can also deepen drought stress and increase the potential for larger, more destructive wildfires.
El Niño is also strengthening in the tropical Pacific. NOAA reported a July Niño-3.4 index near 1.2°C above average and an 81% chance that the event will become very strong during October through December.
However, the immediate driver of this heat wave was the high-pressure ridge over the western states. El Niño can influence broader seasonal weather patterns, but its contribution to this individual event cannot yet be isolated.
