Temperatures in Las Vegas have never hit the century mark in April before, but that’s the forecast for Wednesday, as a record-setting and potentially historic spring heat wave peaks in the Desert Southwest.
The heat wave is due to a zone of intense heat pressure sprawled over the Southwest.
Excessive heat warnings stretch from southwest California into southern Nevada and through much of southern Arizona. The warnings, in effect through Thursday, caution “dangerously hot conditions” are expected.
“These extreme temperatures this early in the season will likely bring significant heat impacts and precautions should be taken to limit exposure to the heat,” wrote the National Weather Service forecast office in Phoenix.
The high temperatures in Phoenix hit the century mark Sunday and Monday and are predicted to remain at or above 100 through at least Friday. The city is likely to put together a streak of six or more consecutive days hitting 100, which would mark the second-longest on record during the month.
Be safe during this Spring heat wave! Temperatures will eventually drop to below 100° this weekend, but remain well above normal readings. #azwx pic.twitter.com/Aqro0wCNWv
— NWS Phoenix (@NWSPhoenix) April 28, 2020
In Las Vegas, the heat is coming on suddenly, after an otherwise cool April. “[I]t’s a rather quick jump to finish out an otherwise below-average month,” the Weather Service forecast office serving Los Angeles tweeted.
As recently as mid-April, highs in Sin City only reached the 60s, while the forecast high on Wednesday is 101 degrees.
The Weather Service tweeted that heat this intense isn’t typical “this early” or “this quickly,” and that “normally we have all spring to acclimate.”
"Excessive Heat Warning? This is the desert! It's supposed to be hot!" 🤔
— NWS Las Vegas (@NWSVegas) April 27, 2020
Actually...not this early nor this quickly. Normally we have all spring to acclimate, so this heat may catch many off guard. 🌡️⬆️
In fact, Vegas should see its first ever 100+ day in April on Wednesday! pic.twitter.com/KhmIglDO5A
Death Valley, the hottest location in the United States, is predicted to hit 110 degrees for the first time this season Wednesday, about three weeks ahead of average, tweeted Weather.com meteorologist Jonathan Erdman.
The heat wave baking the Southwest began late last week, spreading the warmest weather of the season so far to Southern California. Temperatures in the Los Angeles area reached the 80s and 90s over the weekend, some 10 to 20 degrees above normal. Downtown Los Angeles hit 93 degrees Saturday.
Some Californians flocked to the beaches to cool off, much to the dismay of local officials amid the novel coronavirus crisis. As The Washington Post reported Monday:
A battle over beaches is brewing in California, where restless residents under a stay-at-home order that has lasted more than a month ventured out to sunbathe over the weekend in the southern part of the state. Warm weather and what researchers are calling “quarantine fatigue” inspired thousands to crowd beaches in Ventura and Orange counties.Gov. Gavin Newsom (D) scolded the weekend beachgoers on Monday, calling what they did “an example of what not to do.”
The core of the heat will shift eastward toward Texas by the weekend, allowing some modest relief in the Southwest; however, temperatures are forecast to remain slightly above average.
While the current weather pattern has set the stage for this heat wave in the Southwest, it is probably more intense because of climate warming from the long-term buildup of greenhouse gases in the atmosphere.
“Every part of the Southwest experienced higher average temperatures between 2000 and 2015 than the long-term average (1895-2015). Some areas were nearly 2°F warmer than average,” stated a report on climate change indicators from the U.S. Environmental Protection Agency.