Powerful storms move east into Arizona, but with less rain than in California. Here's why
A series of severe winter storms propelled by a merging of powerful atmospheric rivers and fueled by El Niño have rocked Southern California, setting daily records for rainfall across the lower region of the state.
Downtown Los Angeles set a record of 4.10 inches Sunday, breaking the previous 1927 daily record of 2.55 inches. Long Beach airport set a record of 1.50 inches, and Santa Barbara airport received 2.39 inches of rain, breaking the previous record of half an inch in 1990.
But as the storm moves inland, Arizonans can expect weaker systems and less rain. The Phoenix area is on track to receive anywhere from half an inch to an inch, far less than what's fallen in Southern California, though still close to a month's worth in one hit.
Matt Salerno, meteorologist at the National Weather Service in Phoenix, said Phoenix won’t get the same storms and rain totals as much of Southern California simply because of the topography.
“Just due to the fact that we have mountainous terrain around the city, and we are in a low spot of the Valley, the clouds and rain tend to form around us,” Salerno said. “As the winds start blowing from the south, those clouds and precipitation move away from the Valley up towards the mountains.”
Atmospheric rivers deliver heavy rains
Still, what's happened in California is more than just topography. The systems pushing along the West Coast and setting rainfall records are fueled by El Niño and atmospheric rivers.
Atmospheric rivers are aptly named: They are long regions of water vapor in the atmosphere, much like a river in the sky. According to scientists at NASA, atmospheric rivers can move more water than double the flow of the Amazon River.
Californians have been dealing with intense downpours, flooded roads, power outages for hundreds of thousands of people, and even a rare warning for hurricane-force winds.
The storms will lose some of their power as they move eastward.
“These storms hitting California are fueled by the atmospheric river that is streaming along the West Coast,” said Salerno. “The amount of moisture being carried by the river is not going to stay strong enough to make it all the way inland to us here in Phoenix.”
What to expect: Powerful atmospheric river will bring rain, snow across Arizona
Rain will continue through the week, with snow in the mountains
While the Valley may not see as much precipitation as Los Angeles and other parts of the West Coast, Phoenix is still expected to receive widespread rain throughout the lower elevations, with snow falling at higher elevations.
Tom Frieders, a warning coordination meteorologist with the National Weather Service in Phoenix, said the heaviest rainfall throughout the state is expected Tuesday into Wednesday. Significant amounts of snow are expected above 6,500 feet, with the heaviest snowfall starting Tuesday night into Wednesday morning.
Excessive runoff along rivers, creeks, streams, and washes will result in road closures and unsafe recreation in many areas. Flood watches are in effect in southwest Arizona and portions of south-central areas of the state.
Half an inch to an inch of widespread rain across the southwest part of Arizona is expected, with higher levels locally, and up to 1.5 inches across south-central Arizona with locally higher levels coming in through thunderstorms. Phoenix on average sees about 0.87 of an inch of rain during February.
Flagstaff and Williams were forecast to receive 9 to 13 inches of snow, Kachina Village and Munds Park were expecting 9 to 15 inches of snow, and Forest Lakes, near Show Low, could get anywhere from 13 to 19 inches.
Unsettled weather will continue into Saturday, with scattered rains and high elevation snow. The best chances for rain were late Tuesday and most of the day Wednesday. High temperatures will drop from the mid-70s on Monday to the lower 60s and upper 50s by Thursday. Lows in Phoenix will fall into the 40s.
For updated road and weather conditions, visit Arizona Traveler Information, download the AZ 511 app or dial 511.
Caralin Nunes writes about weather and related topics for The Arizona Republic and azcentral. Email her with story tips at caralin.nunes@arizonarepublic.com.
This article originally appeared on Arizona Republic: Why storms won't hammer Arizona like they did California
