Western U.S. Braces for Record Heatwave

A significant early-season heatwave is impacting the Western United States, with temperatures projected to be 20-30 degrees Fahrenheit above normal from Thursday through next week. This weather event, driven by a persistent high-pressure system, is expected to shatter daily and potentially all-time March temperature records in Southern California and other states. The National Weather Service indicates that approximately 26.4 million people will face moderate heat risks by Tuesday, with tens of thousands potentially experiencing extreme heat.

The heatwave commenced on the West Coast on Thursday, extending across California, Nevada, Arizona, and New Mexico. A more intense second wave is forecast to begin Monday, reaching Utah, Colorado, Oregon, Idaho, and Wyoming. Temperatures could exceed 100°F (37.8°C) in Los Angeles, reach 90°F (32.2°C) in the San Francisco Bay Area, and potentially hit 110°F (43.3°C) in southeastern deserts. This early-year heat poses heightened public health risks as bodies are not acclimated to such conditions.

Furthermore, the elevated temperatures are expected to accelerate snowmelt, exacerbating concerns over already low snowpack levels following the warmest winter on record in much of the region. This rapid snowmelt could lead to the worst spring snowpack on record for many Western U.S. watersheds, intensifying drought conditions and increasing wildfire risks.