NOAA Predicts Warm, Wet Winter From A Weak El Nino

Written by Sue Wood on October 22, 2018. Posted in Current News

With most of the United States expected to experience above-average temperatures this winter, California will stay on the extreme track with El Nino predicted to move us from drought conditions in the fall to more atmospheric rivers from December into February 2019.

The National Oceanic and Atmospheric Administration released its winter outlook, placing California’s midsection as having an equal chance of more precipitation than other years and warmer than usual.

This means less snowpack in the Sierra Nevada mountain range –and for what comes down, it may be hard to manage. Sometimes too much, too fast is detrimental to our water supply that municipalities and farmers rely on.

“The bulk of the rainfall could be in atmospheric rivers. Expect to see some number of those with the warming of the ocean,” NOAA Climate Prediction Center Deputy Director Mark Halpert said.

El Nino is a tropical weather phenomenon that originates off the shores of South America with warm water masses that affect the climate.

It commonly brings less rain to the Pacific Northwest and more rain to Southern California — with the Bay Area on the cusp.

But in this vertical state, the forecast is more complex than that. Some weather oscillations may contribute more to the “heavy precipitation” than even the El Nino this winter.

“California’s tricky,” Halpert told Patch on a media conference call. He further dictated a concern that “snow levels typically rise” — especially when atmospheric rivers pound the snowpack and carry it away when the rainfall comes all at once. “What makes and breaks them is the number of them,” he added.

More are expected to hit this winter. Normally, California experiences about eight of these prolonged poundings. They have labeled these Pineapple Express storms because they’re tropical in nature and release their torrent fast and furious.

Granted, this fall is witnessing a 70 percent build-out of a weaker El Nino. However, El Ninos more often than not bring heavy precipitation with drenching rain pounding the streets, flooding the airports, uprooting trees and creating havoc for homeowners.

Sandbags could be the order of the day. Cities like Palo Alto prepare with their two stations at Rinconada and Mitchell parks established and ready to go before winter hits in its fury, city spokeswoman Claudia Keith confirmed.

Jon Hospitalier of Public Works manages crews responsible for placing 3,000 catch basins throughout the city by Dec. 1 and clean out the already-installed trash-capture devices that resemble baskets in the problem areas where garbage collects.

The department also works on hydro flushing the stormwater system to deter from a backup.

“El Nino is difficult to predict. We’ve had flooding in the past. Back in 1998 during an El Nino, we lost about 70 homes. It’s all about cleaning things up to make sure things are flowing correctly,” the assistant director said.

Still, fall may pose the other extreme — which isn’t good news for firefighters. October was the month that brought the worst cluster ever of wildland fires in the Bay Area.

Firefighters can’t win for trying. It’s bad when the grass, brush, and trees are timber-box dry. It’s also bad when heavy precipitation grows the level of fuel to burn.

“As we head into winter, drought conditions are a concern for large parts of the West,” Halpert said. When the rain does pour, it flows every which way over a solid ground.

There is a connection between the warmth and El Nino. On average, the stronger the El Nino episode, the warmer and wetter the winters have been. The winter of 2015-16 brought one of the strongest El Ninos in the past 60 years.

“It was also the warmest winter on record for the continental United States,” Halpert said.

The other two “very strong years” were 1982-83 and 1997-98.

Read more at Patch

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