El Nino expected to bring rain this summer
The hot temperatures are expected to continue on through the summer as well as bringing rain and thunderstorms to the Yuma region.
Forecasters say part of the reason Arizona had so many storms this winter was a climatological pattern known as El Niño when surface temperatures in the equatorial Pacific Ocean are warmer than normal.
“When this happens, this can affect the weather patterns downstream and into the United States, particularly during the winter season,” said Mark O’ Malley with the National Weather Service office in Phoenix.
El Niños, which occur every two to seven years, beginning in the fall, a peak that winter and normally dissipate by spring, the National Oceanic and Atmospheric Administration says. The name in Spanish means “the boy,” a reference to the infant Jesus. The opposite phenomenon is La Niña: when surface temperatures in the equatorial Pacific are cooler than normal.
Normally, El Niño does not last through the summer, but when it does, it can affect weather across the U.S., just as it does during the winter. However, in Arizona, the forecast can get tricky.
“Unfortunately, its predictability becomes very low during the summer season,” O’ Malley said. “We just don’t have a lot of historical precedents to build our forecast on.”
It’s hard to say what all of this will mean for Arizona’s summer monsoon.
NOAA’s records show there have only been seven lingering El Niño events in the past 69 years. Comparing those events with the wettest monsoons at Phoenix Sky Harbor, only two coincide with a lingering El Niño.
Historically, there is not much to prove that there’s a connection between the monsoon and El Niño.
“It doesn’t necessarily lead to a wetter or drier monsoon season; it is just too difficult to say,” O’ Malley said.
O’ Malley said it’s a guessing game whether Arizona could see more rain this summer, but he said regardless, people should be prepared for large storms that could come from potential hurricanes.
“It only takes one big hurricane to make a difference, so just because there may be less of them, doesn’t make it any less of a threat.”
