Maps show forecast for extreme heat wave scorching the West A prolonged heat wave is intensifying across the western United States, with temperatures expected to remain dangerously high for several days. A persistent high-pressure system is suppressing precipitation and creating conditions for early-season extreme heat, affecting regions from the Desert Southwest to coastal areas near the Pacific Ocean. Triple-digit temperatures are already scorching cities like Palm Springs, California, where a record 103 degrees was recorded Tuesday. Phoenix, Arizona, also experienced its earliest-ever 100-degree high on Wednesday, breaking the previous record set in 1988. This marks the first such temperature in the city since record-keeping began in 1896. The National Weather Service warns that above-normal temperatures will persist through the weekend, with additional record-breaking daily highs and overnight lows likely. Forecasters predict the heat could extend into early next week, raising concerns about prolonged exposure to extreme conditions. The situation has prompted extreme heat warnings and advisories across the Southwest, including major cities such as San Francisco, Los Angeles, San Diego, Las Vegas, and Tucson. These alerts are in place through at least Sunday, with potential for extensions. Technically, a heat wave is defined as a period of unusually hot weather lasting two or more days, with temperatures significantly above historical averages for a given region. While 100-degree temperatures are common in Phoenix during summer, they are classified as a heat wave in early spring. The National Weather Service emphasizes that such conditions pose significant risks, particularly for vulnerable populations.#national_weather_service #los_angeles #san_francisco #phoenix_arizona #palm_springs_california
