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California Experiences Fifth Straight Month of Below Average Snow, Precipitation

The Department of Water Resources today conducted the third manual snow survey of the season at Phillips Station. The manual survey recorded 56 inches of snow depth and a snow water equivalent (SWE) of 21 inches, which is 86% of average for this location. The SWE measures the amount of water contained in the snowpack and is a key component of DWR’s water supply forecast.

“As California closes out the fifth consecutive dry month of our water year, absent a series of strong storms in March or April we are going to end with a critically dry year on the heels of last year’s dry conditions,” said DWR Director Karla Nemeth. “With back-to-back dry years, water efficiency and drought preparedness are more important than ever for communities, agriculture and the environment.”

Why All that Snow We’re Shoveling May Not Rescue Utah from a Bad Water Year

Old Man Winter has been busy of late, bringing much-needed relief to Utah’s dangerously low snowpacks. But don’t let the piles of fresh snow fool you. After near-record low precipitation over the past year, Utah water supplies remain in serious trouble even with the recent return of long-absent wet weather.

Precipitation Below Average in California

Precipitation is below average in California for the current water year. Despite recent storms that increased the statewide Sierra Nevada snowpack to 70% of average to date, the state is experiencing its second consecutive below average year for rain and snow.

California’s Rainy Season Starting Nearly a Month Later Than it Did 60 Years Ago

The start of California’s annual rainy season has been pushed back from November to December, prolonging the state’s increasingly destructive wildfire season by nearly a month, according to new research. The study cannot confirm the shift is connected to climate change, but the results are consistent with climate models that predict drier autumns for California in a warming climate, according to the authors.

Precipitation-Snowpack Survey-Sierra Nevada-DWR

Precipitation Below Average in California

Precipitation is below average in California for the current water year. Despite recent storms that increased the statewide Sierra Nevada snowpack to 70% of average to date, the state is experiencing its second consecutive below average year for rain and snow. The water year starts on October 1 and ends September 30.

The Department of Water Resources Feb. 3 conducted the second manual snow survey of the season at Phillips Station. The manual survey recorded 63 inches of snow depth and a snow water equivalent, or SWE, of 17 inches, which is 93% of average for that location, according to the DWR. The SWE measures the amount of water contained in the snowpack and is a key component of DWR’s water supply forecast.

“The recent blast of winter weather was a welcome sight, but it was not enough to offset this winter’s dry start,” said DWR Director Karla Nemeth. “While there is still a chance we will see additional storms in the coming weeks, the Department and other state agencies are preparing for the potential for a second consecutive year of dry conditions.”

 La Niña-Sierra Nevada-snowpack-climate-snow survey

Below normal precipitation is favored throughout most of the southern tier of the United States in late February to early March, according to the National Weather Service Climate Prediction Center. La Niña conditions remain over the Pacific Ocean.

Precipitation below normal

Statewide snow survey measurements reflect those dry conditions. Measurements from DWR’s electronic snow survey stations indicate that statewide the snowpack’s SWE is 12.5 inches, or 70% of the February 3 average, and 45% of the April 1 average. April 1 is typically when California’s snowpack is the deepest and has the highest SWE.

“The recent atmospheric storms have brought rain and snow to the northern Sierra Nevada, but conditions are still well below normal,” said Goldy Herbon, San Diego County Water Authority senior resources specialist.

Following last year’s below average water year, northern California is now experiencing its second straight water year of below average precipitation.

Colorado River Basin

Another source of the state’s water supply, the Colorado River Basin, isn’t faring much better. The water year 2021 precipitation at the end of January for the Colorado River Basin is 66% of normal, according to the U.S. Bureau of Reclamation.

Precipitation totals to date are behind historical averages for two of the main sources of San Diego County’s supply, with two months to go in the winter season but, a couple of atmospheric rivers can change that quickly.

“The San Diego region will have a plentiful and reliable source of water due to actions taken by the Water Authority and its 24 member agencies to diversify the water supply,” said Herbon. “Continuing efforts to expand supply sources, including desalination, water reuse, and recycling, will ensure that the water needs are met for the region’s 3.3 million people and its $245 billion economy.”

Fall 2020 was extremely dry, especially in the Sierra Nevada, and follows last year’s below-average snow and precipitation, according to the DWR. With only a couple months remaining in California’s traditional wet season, DWR officials say Californians should look at ways to reduce water use at home.

snowpack-reservoirs-Snow survey

Statewide Sierra Nevada snowpack is 71% of average for February 4, 2021. Graphic: California Department of Water Resources

Will the Storm Move the Drought Needle?

Bay Area water agencies, starved for snow and rain, are encouraged by this week’s storm system.

But managers say it’s too early to say if it will have a lasting impact.

Drought Conditions Continue in California Due to a La Niña Weather Pattern

We had a very late start to the rainy season this year, similar to what we have seen in recent years. We’ve seen about one-third of the normal rainfall for the current date—well below the normal amount. There could be a weather pattern explaining some of the lack of rain. That is called a La Niña weather pattern.

U.S. Flood Damage Rose 30% in 30 years, a Sign of Warming

Increased precipitation resulting partially from climate change has caused an additional $2.5 billion a year in U.S. flood damage, according to a new study that pinpoints the effect of changing weather on the cost of natural disasters.

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.

Utah’s Water Year So Far, and Why People Should ‘Think Snow’

So far this water year that began Oct. 1 has been treating most of Utah like a miserly scrooge, stingy with storms and the accompanying snow. The southern half of the state, as of Monday, was sitting in the 60% of normal accumulation of snowpack, and the Lower Sevier River Basin at 36% of normal is experiencing abysmally dry conditions.