Tag Archive for: Weather

Why It’s Way Too Early to Worry About Rain Deficits in SoCal

Yes, it’s been pretty dry so far this winter, but there is no need to worry. The major winter storm that roared through Southern California Monday proved we can erase a month’s worth of rain deficit in one day. I recently explained how the climate where we live — the Mediterranean Climate — sees the majority of its annual rainfall in the winter months. In fact, a whopping 80% of Southern California’s annual rain and snow falls from December through March.

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Dry Start to California’s Water Year

A dry start to California’s water year is reflected in the season’s first snow survey of the Sierra Nevada snowpack. The statewide snowpack is 52% of average for Dec. 30. On average, the Sierra snowpack supplies about 30% of California’s water needs.

The California Department of Water Resources manual survey at Phillips Station recorded 30.5 inches of snow depth and a snow water equivalent of 10.5 inches, which is 93% of the January 1 average at that location, according to DWR officials. The snow water equivalent,or SWE, measures the amount of water contained in the snowpack and is a key component of DWR’s water supply forecast.

While the Phillips Station measurement was positive, DWR’s electronic readings from 130 stations placed throughout California show the statewide snowpack’s SWE is 5 inches, or 52% of the December 30 average.

“The snow survey results reflect California’s dry start to the water year and provide an important reminder that our state’s variable weather conditions are made more extreme by climate change,” said DWR Director Karla Nemeth. “We still have several months left to bring us up to average, but we should prepare now for extended dry conditions. The Department, along with other state agencies and local water districts, is prepared to support communities should conditions remain dry.”

Water supply diversity meets regional demand

“The first snowpack survey of the water year points to California’s climate variability, which is why a diverse water portfolio is needed to provide a reliable supply,” said Goldy Herbon, San Diego County Water Authority senior water resources specialist. “The Water Authority and its 24 member agencies have successfully diversified water sources, and continue to expand those sources, to ensure our supply meets the needs of the region’s 3.3 million people and its $245 billion economy.”

The supply sources include water from the Claude “Bud” Lewis Carlsbad Desalination Plant, where ten workers volunteered to live on-site in 2020 to keep the water flowing during the coronavirus pandemic.

Sierra Nevada Snowpack-Snow Water Content

Climate change brings less snow

When the Sierra Nevada snowpack melts, it feeds into rivers and is stored in reservoirs across California. Reservoirs are tapped as needed during the dry months. However, state officials again said that climate change is affecting California’s snowpack, as more precipitation falls as rain and less as snow. And they urged Californians to make water conservation a “way of life.”

“Today’s survey brought a first glimpse of how the state’s snowpack is shaping up, but there is a lot of winter still ahead,” said Sean de Guzman, chief of DWR’s Snow Surveys and Water Supply Forecasting Section. “While the dry conditions during late summer and fall have led to a below average snowpack, it is still encouraging to have the amount of snow we already have with two of the three typically wettest months still to come.”

DWR conducts five snow surveys at Phillips Station each winter near the first of each month, January through April and, if necessary, May. Guzman said the next survey is scheduled for February 2.

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Sean De Guzman (R), chief of the California Department of Water Resources Snow Surveys and Water Supply Forecasting Section, and Jeremy Hill, DWR water resources engineer, conduct the first snow survey of the 2021 season at Phillips Station in the Sierra Nevada. Photo: Kelly M. Grow/DWR

Dismal California Snowpack is Bad Sign for Water Supplies

A month into California’s peak storm season, the lack of wet weather is beginning to weigh on the state’s water supply.

The snowpack in the Sierra and southern Cascades, which provides as much as a third of the water used by California cities and farms, is about 55% of average for this time of year. It hasn’t been this low at this time since 2017, when the state was emerging from a five-year drought.

San Diego’s First Winter Storm Drops Snow in Mountains, Rain Elsewhere

A Monday storm that dumped much-needed rain and snow across San Diego County was expected to peter out overnight into Tuesday, according to the National Weather Service in San Diego.

Monday’s storm brought the county’s first significant traces of precipitation since the first week of November, when a North Pacific storm dropped several inches of snow in the mountains and some rain off to the west.

Southern California Experiences La Niña-Related Dry Spell

Barely any rain and it’s already mid-December? Malibu is experiencing drought conditions—but a drought it is not. That’s a key difference: a “drought” can actually only be declared by the Governor of California; his declaration releases key relief funding for several agencies. “Drought conditions,” on the other hand, is a classification that marks a series of factors that could lead to a drought down the line. 

First Snow Survey of the 2020-21 Season Coming December 30

California’s first snow survey of the 2020-21 season is happening Dec. 30 at the Phillips snow course in the Sierra Nevada.

The Department of Water Resources will conduct five of these surveys through May by plunging a long steel tube into the snow. This will measure the snow’s depth and give an estimate of its water content.

Scientists Use New Methods to Better Forecast Atmospheric Rivers

Earlier this year, the Center for Western Weather and Water Extremes launched a new sub-seasonal to seasonal forecast product to better predict the influence atmospheric rivers will have on the Western United States. Better and more accurate forecasting tools for atmospheric rivers are critical for a number of community uses, including water management, agriculture, insurance and commodities trading, to name a few.

The demand for better atmospheric forecasting tools has facilitated the development of the new S2S forecasting products launched by CW3E this year.

Waves Off Central Coast Contain Clues About Changing Climate. Is California Due for Drought?

The waves along the Central Coast can tell you a lot about our changing climate, and here’s why.

The Diablo Canyon Power Plant’s Waverider Buoy has measured wave heights and periods since June 1983 and directions since June 1996 and is one of the longest continuous-wave monitoring stations along the West Coast.

Scripps Institute of Oceanography’s Coastal Data Information Program maintains an extensive network of buoys that monitor waves along the coastlines of the United States. You can view the historical wave data archive from Diablo Canyon and other stations at the CDIP database at cdip.ucsd.edu.

Colorado River Basin Winter Forecast Signals Dry Times Ahead

All signs are pointing to a dry start to 2021 across much of the Colorado River watershed, which provides water to about 40 million people in the Western U.S.

A lack of precipitation from April to October made this spring, summer and fall one of the region’s driest six-month periods on record. And with a dry start to winter, river forecasters feel more pessimistic about the chances for a drought recovery in the early part of 2021.

November 2020 Was Second Hottest November on Record

The nation’s climate scientists say November was warmer than usual, and it was yet another month in a pattern of rising global temperatures. The National Oceanic and Atmospheric Administration tracks global temperatures and researchers say the warming trend is continuing.