This winter was the warmest in recorded history for the West.- Next week, record-breaking heat will descend across most of the Southwest.
- Salt Lake City can expect temperatures in the 80s, with some places experiencing triple digits.
Following what was the warmest winter ever recorded for much of the American West, a record-breaking heat wave is set to settle over western states in the coming days.
“We are about to experience the hottest March temperatures that we’ve ever seen across a lot of the western U.S.,” said Daniel Swain, a weather and climate scientist at the University of California.
“This is one of those years where it’s extremely noticeable. You really have to go out of your way to avoid the conspicuousness this year of how off things tangibly feel.”
Compared to previous years, most temperatures will not be above previous records by just a few degrees; they’ll be above by as many as five to 10 degrees. Parts of the Southwest are forecast to experience temperatures 30 degrees above normal March averages.
In Salt Lake City, it’s already pushing 70 degrees this week, and the anticipation is that they’ll reach the 80s by the middle of next, according to the National Oceanic and Atmospheric Administration. The average temperature for March is the mid-to-upper 50s.
In southern Utah, St. George is forecast to reach just shy of 100 degrees by Thursday. Its historical March average is 53 degrees.
Things are far more intense in Los Angeles, where temperatures are already in the 90s and might reach into the triple digits over the weekend. Phoenix, too, is set to reach into the 100s as well.
These numbers don’t seem too high?
While some of the top degree numbers may not be the highest that much of the West has ever experienced, it’s helpful to consider how early in the year it is. By early next week, temperatures across the West will be those of an early to mid-summer season, rather than the end of winter.
“The forecast for next week suggests that a good portion of the Southwest might experience its most extreme March heat wave ever observed,” Swain said. “A lot of locations will experience their hottest temperature ever observed for the entire month of March — in the first half of the month, notably."
Swain said it’s easier to break monthly records toward the end of the month, but a lot of locations will have the hottest temperatures they’ve ever experienced this early in a calendar year.
“Earliest 100 degree, earliest 90 degree, earliest 80 degree, depending on how high up the mountain slope you go and what your averages are,” Swain said. “Records will be set.”
What about a miracle march?
After a tough winter for snow or precipitation — which this winter was hot, not necessarily low on rainfall — the idea that a rainy spring might make up the difference is a common thought that folks will bring up.
Swain does not think that’s going to happen.
“A lot of folks like to talk about the notion of a ‘miracle March,’” Swain said. “This year that is not going to happen. There will be no miracle March.”
That is because forecasts suggest these temperatures are going to stick around for some time.
“This is not going to be a short-duration heatwave, but it looks like it’s pretty much going to last for the foreseeable future. It looks like it’s going to be a 10- to 14-day stretch of extraordinarily anomalous weather,” Swain said in a digital office hours he hosts on YouTube. “It won’t be equally hot the whole time everywhere — we’ll shift around the peak maximums around the West — but it just looks, again, really extraordinary.”
The bigger picture
While the temperatures themselves are going to be very difficult for many people, municipalities and states west of the Rockies, the bigger picture of this winter and the coming heat wave will be the story of water.
More than half of the West’s water comes from snow, Bea Gordon, a research professor in hydrologic sciences and engineering at the Deseret Research Institute, said. She noted that the snowpack is this gigantic and free reservoir that the entire western United States relies on — one that distributes right on time for our needs.
“Historically, that’s meant that we get water closer to the time when our demand is highest because it melts in May, June and then our our demand peaks,” Gordon said. “But in years like this, we don’t have any of that reservoir.”
Without the snowpack, which this heat wave is going to likely melt out much earlier than normal, the West will need to find a reservoir to compensate for the loss.
“So much about how the Western U.S., our legal infrastructure, our physical infrastructure, everything is built around this giant free reservoir that we have in snowpack,” Gordon said. “When we don’t have that, it makes us, you know, it strains our infrastructure.”
As Swain understands this loss of the snowpack, effects are going to compound existing issues.
“The Colorado River watershed has been in trouble for some time. That’s not new. The Great Salt Lake has been in dire straits for some time. That’s not new,” Swain said. “There’s a combination of reasons for this. One is that there’s way more demand for water than there is water. That’s happening at the same time that the actual amount of water, even as demand grows, is actually decreasing.”
That is all exacerbated, he said, by the “really severe, long-term, multi-decadal droughts” that are a result of the longterm warming that the West has been facing.
“There is a big climate change component to this. It’s certainly not the only relevant piece, but the problem is, in some years it’s subtle, and in some years it’s very unsubtle,” Swain said. “And this is one of those unsubtle years where this is ‘the uh-oh moment.’”
