Jul 2, 2017

Monsoon picking up over Southwest; heat & moisture across much of CA

California
USA
by
Daniel Swain
,
California Weather Blog
Summer has been off to a very hot start across nearly all of CA away from the immediate coastline. Image: WRCC
Summer has been off to a very hot start across nearly all of CA away from the immediate coastline. Image: WRCC

After a relatively mild spring across most of California, June brought quite the reversal. A prolonged, record-breaking, and unusually “muggy” heatwave enveloped nearly all of California for multiple weeks, and temperatures have only fallen back to average over the past few days. This remarkable early-season heatwave set innumerable daily temperature records across the American Southwest, tied or broke several June monthly records, and actually exceeded or tied the hottest temperature on record at a handful of sites (including Needles, CA and Las Vegas, NV). The very prolonged nature of the heat, combined with the presence of an unusually humid airmass over Northern California, made the human impact of the heat even worse–and also led to consecutive “hot day” and record warm overnight temperature records being set in a number of locations.