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This Year’s Snow Season Wipes Away Drought in Much of the West

The 2022–2023 snow season started off relatively active across the West, with a few modest storms bringing snow accumulations to the mountains in early November. By the start of December, snow water equivalent across much of the region was above normal.

Feds Announce Start of Public Process to Reshape Key Rules on Colorado River Water Use by 2027

A public process started Thursday to reshape the way Colorado River water is distributed, with federal officials promising to collect comments about updating and enacting rules in 2027 to continue providing hydropower, drinking water and irrigation to farms, cities and tribes in seven Western U.S. states and Mexico.

The U.S. Interior Department said it will publish in the Federal Register on Friday a call for replacing guidelines that expire in 2026, including pacts enacted in 2007 for states to share cutbacks in water drawn from a river diminished by drought and climate change, as well as operating plans for the key Lake Powell and Lake Mead reservoirs. An agreement between the United States and Mexico on use of Colorado River water also is set to expire at that time.

The department’s U.S. Bureau of Reclamation promised a “robust and transparent public process” beginning with online virtual public meetings July 17July 18 and July 24. It set an Aug. 15 deadline for receipt of public comments on “specific operational guidelines, strategies and any other issues that should be considered.”

San Diego County Water Authority And its 24 Member Agencies

Water Authority Board Holds Public Hearing on 2024 Wholesale Water Rates

June 15, 2023 – On June 22, the San Diego County Water Authority Board of Directors will hold a public hearing about proposed wholesale water rates for 2024, followed by votes on the rate proposal and the recommended budget for the next two fiscal years.

The Water Authority Board is seeking to manage cost increases created by extraordinary inflationary pressures and depressed water sales, while at the same time protecting ratepayers, ensuring water reliability, and maintaining the Water Authority’s strong credit ratings that reduce the life-cycle cost of infrastructure. Due to its long-term commitment to strategic financial management, the Water Authority has senior lien credit ratings of AAA from Standard & Poor’s, AA+ from Fitch ratings and Aa2 from Moody’s.

The public hearing is scheduled to start when the Administrative and Finance Committee meets at 9 a.m. June 22, at 4677 Overland Avenue in San Diego. The hearing will also be livestreamed at www.sdcwa.org/about-us/board-of-directors/meetings/. Public comments will be accepted in person; via Zoom at https://us06web.zoom.us/j/83333513511?pwd=SW9VU0NQaDd3aHlsMlN4ajluUkp4dz09#success with passcode 576222; or by phone at 669-444-9171 using meeting ID 833 3351 3511# and passcode *576222# as prompted.

drought relief-snowpack-West-NIDIS winter update

This Year’s Snow Season Wipes Away Drought in Much of the West

The 2022–2023 snow season started off relatively active across the West, with a few modest storms bringing snow accumulations to the mountains in early November.

By the start of December, snow water equivalent (SWE) across much of the region was above normal. Starting in early December, several storm cycles brought moisture-laden families of atmospheric rivers to the West Coast. Most of the landfalls occurred in California. The strongest series of storms occurred steadily from December 27 through January 17.

By the end of January, SNOTEL sites across much of the Sierra Nevada, Great Basin, Utah, Arizona, and western Colorado were at >150% of normal SWE. Unlike the 2021–2022 water year, in which snowfall was abundant early in winter but scarce after early January, the storm train continued with another series of strong storms across the West from late February through mid-March.

By April 1, snowpack was above normal across nearly the entire West, with few areas of snow drought. In some parts of the Sierra Nevada, Great Basin, Utah, Arizona, and western Colorado, SWE reached 200%–300% of normal and, in certain locations, set records. The northern Pacific Northwest and northwestern Montana was on the periphery of the storm track during most of winter. In these areas, snow drought developed as snowmelt began, and summer drought conditions are developing or seem likely to develop.

Key Points

  • An above-normal start to winter precipitation in the West—with the exception of the Pacific Northwest—accelerated when a series of 9 atmospheric rivers over a 3 week period brought significant amounts of rain and snow. The precipitation pattern this year was unlike that of last year, when the fire hose of storms shut off in January.
  • In the Sierra Nevada, Great Basin, and Colorado River Basin, the cool, wet, and snowy year brought major drought relief. As of mid-June, observed water year runoff has been above normal, and forecasts indicate that above-normal summer flows will persist.
  • Higher-elevation snowpack across the West remains, and is remarkably deep for mid-June in parts of the Sierra Nevada and southern Cascades.
  • Persistent and widespread anomalously cold winter temperatures, which have not occurred in recent years, aided snowpack development.
  • Lakes Powell and Mead, the two largest reservoirs in the country, have benefited this year, but it will take much more than one wet year to refill them after over 20 years of decreasing water levels.
  • Rapid snowmelt and early melt out have been problematic in parts of the Pacific Northwest. Abnormal dryness (D0) and moderate drought (D1) reappeared in Washington and Oregon over the past three weeks.
  • El Niño conditions have developed and are expected to gradually strengthen into winter. A stronger El Niño means global temperature, precipitation, and other patterns are more likely to reflect the expected El Niño impacts, such as wetter conditions in the southern U.S. and warmer conditions in the northern U.S. Historically, impacts from the transition to El Niño begin to be felt in early fall.

Abnormally cold temperatures persistent and widespread in winter 2022-23

During the past winter, unlike many recent years, anomalously cold temperatures were persistent and widespread. November through March temperatures were among the lowest third of all years since 1895 across much of the West. Temperatures in parts of California, Nevada, Oregon, and Idaho were among the coldest ten percent. Impacts of the cold temperatures included an unusual proportion of precipitation falling as snow compared to rain, snow persisting at lower elevations for longer than usual, and little mid-winter snow melt at higher elevations.

Drying and warming trend in April

April brought a drying and warming trend to the Southwest and above-normal precipitation and cooler temperatures to Oregon and Washington, reducing some of the snowpack deficits in the Cascade Range. However, the cool and wet conditions in the Pacific Northwest were short-lived. Throughout May and into early June, temperatures across the Pacific Northwest and northern Rocky Mountains were above normal, with record warmth in parts of northern Oregon, Washington, northern Idaho, and northwestern Montana. The warm temperatures combined with relatively dry conditions have led to rapid snow loss across the region, and snow has melted one to three weeks early at many SNOTEL stations (70 sites in Oregon, Washington, Idaho, and Montana melted out more than a week early).

May snowmelt

May snowmelt reached record highs across many western regions, not just the Pacific Northwest. However, in terms of drought development, the early snowmelt was only problematic for parts of the Pacific Northwest and northern Rocky Mountains, where snowpack at the beginning of May was near normal or below normal (unlike the near-record snowpack in the Sierra Nevada, Utah, and western Colorado). The rapid snow loss, low winter precipitation, and forecasted below-normal summer runoff have renewed concerns about drought in the Pacific Northwest, with abnormal dryness (D0) and moderate drought (D1) reappearing in portions of western Washington and Oregon over the past three weeks.

Snowpack “remarkably deep” for mid-June

Currently, snowpack persists at higher elevations throughout the West and remains remarkably deep for mid-June in parts of the Sierra Nevada and southern Cascade Range. A few notable locations include Leavitt Lake in the central Sierra Nevada, with 92 inches of SWE remaining as of June 12; Lower Lassen Peak in the southern Cascade Range, with 82 inches of SWE remaining; and Mount Rose Ski Area near Lake Tahoe, with 43 inches of SWE remaining.

Drought relief in California and Colorado River Basin

For California, the Great Basin, and the Colorado River Basin, the cool, wet, and snowy year brought major drought relief after three consecutive dry years. Observed water year runoff in these regions was above normal through early June, and the forecasts indicate above-normal flows persisting throughout summer.

Lake Powell and Lake Mead

Major reservoirs, with the exception of Lakes Powell and Mead, have already filled or are expected to fill by the end of summer. This year was still beneficial for Lakes Powell and Mead, the two largest reservoirs in the country, but it will take much more than one wet year to refill these reservoirs after over 20 years of falling water levels. The June 12th update from the U.S. Bureau of Reclamation indicated that Lake Powell was at 37% of capacity and Lake Mead was at 31% of capacity, with forecasted April–July inflows into Powell at 167% of normal.

(Editor’s Note: NIDIS and its partners launched this snow drought effort in 2018 to provide data, maps, and tools for monitoring snow drought and its impacts as well as communicating the status of snow drought across the United States, including Alaska. Thank you to our partners for your continued support of this effort and review of these updates. For more information contact: Daniel McEvoy, Western Regional Climate Center, Amanda Sheffield, NOAA/NIDIS California-Nevada Regional Drought Information Coordinator, and Britt Parker, NOAA/NIDIS Pacific Northwest Regional Drought Information Coordinator: www.drought.gov/drought-status-updates/water-year-2023-snow-drought-conditions-summary-and-impacts-west-2023-06-15)

Don’t Be Fooled by Rain and Snow, the Colorado River is Still in Serious Trouble, Experts Say

Water is rushing from Colorado’s Western Slope and into the tributaries of the Colorado River, restoring reservoirs across the American West to perhaps a semblance of their former glory. Cities, farmers, ranchers and water managers are breathing a sigh of relief at the crisis avoided this summer thanks to the robust snowfall this winter.

‘Climate Whiplash’ is the New Normal for California, Experts Say

Summer is approaching in California, and warmer temperatures have been melting the massive snowpack dumped on the state over the winter. Several swimmers and kayakers drowned this spring as rivers flooded and raged. The National Park Service took the rare step of closing much of Yosemite National Park’s scenic valley for several days to protect hikers and campers from floods. In April, California snowpack was at 237% of the average.

Snowpack Buys Utah’s Water Supply Some Time but Planning for a Drier Future is Key

The high Utah mountains gained 30 inches of water this winter, compared to 12 inches the year before. That amount of water in one season has done wonders for Utah’s ongoing drought.

“This time last year, about 99% of the state was in severe drought,” said Laura Haskell, the drought coordinator with the Utah Division of Water Resources. “So we have just about 14% [that] is in the moderate drought category. And that’s it.”

Map Shows Epic Amounts of Water Gushing Through California’s Rivers

This year’s historic snowpack has meant epic amounts of water flowing through California’s rivers, streams and creeks. … That’s more than the capacity of four standard 40-foot shipping containers rushing by each second. Around 40% of the roughly 500 stream gauges across the state are running above normal, provisional data from the U.S. Geological Survey shows. A few dozen are registering record highs for this time of year, especially along the central and southern Sierra. With peak melt season expected in the coming weeks, this means plentiful amounts of water running into reservoirs, but also dangerously fast flows and the risk for potential flooding.

California snowlines-Scripps Institution of Oceanography-study-Climate Change

California Snowlines On Track To Be 1,600 Feet Higher by Century’s End

This winter produced record snowfall in California, but a new study suggests the state should expect gradually declining snowpacks, even if punctuated with occasional epic snowfalls, in the future.

An analysis by Tamara Shulgina, Alexander Gershunov, and other climate scientists at UC San Diego’s Scripps Institution of Oceanography suggest that in the face of unabated global warming, the snowlines marking where rainfall turns to snow have been rising significantly over the past 70 years. Projections by the researchers suggest the trend will continue with snowlines rising hundreds of meters higher by the second half of this century.

California snowlines and lower-elevation ski resorts

In the high Southern Sierra Nevada range, for instance, snowlines are projected to rise by more than 500 meters (1,600 feet) and even more when the mountains get precipitation from atmospheric rivers, jets of water vapor that are becoming an increasingly potent source of the state’s water supply.

“In an average year, the snowpack will be increasingly confined to the peak of winter and to the highest elevations,” the study says.

Diminished snowfall is a consequence of a changing climate in which places like California will get an increasing portion of their winter precipitation as rain instead of snow. The authors said this study and related research suggest water resource managers will need to adapt to a feast-or-famine future. California’s water supply will arrive less through the gradual melt of mountain snowpack that gets the state through hot summers and more via bursts of rain and runoff delivered by atmospheric rivers, which are boosted by warming and are associated with higher snowlines than other storms.

Warmer summers

Such events will further complicate the balancing act between protecting people and infrastructure from winter flooding and ensuring enough water supply during warmer summers.

“This work adds insight into the climate change narrative of more rain and less snow,” said California Department of Water Resources Climatologist Mike Anderson. “DWR appreciates our partnership with Scripps to help water managers develop, refine, and implement adaptation efforts as the world continues to warm and climate change impacts are realized.”

The study, funded by the U.S. Bureau of Reclamation and the DWR, appears in the journal Climate Dynamics today.

“This is the longest and most detailed account of snow accumulation in California,” said Gershunov, “resolving individual storms over 70 years of observed weather combined with projections out to 2100.”

Climate change impacts to ski industry

The authors make note of what this could mean for ski resorts around the state if climate change progresses unabated. For example, Mammoth Mountain, at an elevation between 2,400 and 3,300 meters (7,900 – 11,000 feet), is projected to receive 28 percent less snowfall in the latter half of the century. Lower elevation ski resorts such as Palisades and Northstar, both near Lake Tahoe, span elevational ranges of around 1,900 and 2,700 meters (6,200 – 8,900 feet). They are projected to lose more than 70 percent of their snow accumulation in an average winter.

“Snowlines will keep lifting”

“Observations and future climate projections show that already rising snowlines will keep lifting,” said Gershunov. “Epic winters will still be possible, though, and unprecedented snowfalls will ironically become more likely due to wetter atmospheric rivers, but they will be increasingly confined to the peak of winter and to the highest elevations of the Southern Sierra Nevada.”

Study co-authors include Kristen Guirguis, Daniel Cayan, David Pierce, Michael Dettinger, and F. Martin Ralph of Scripps Oceanography, Benjamin Hatchett of the Desert Research Institute of Reno, Nev., Aneesh Subramanian of University of Colorado at Boulder, Steven Margulis and Yiwen Fang of UCLA, and Michael L. Anderson of the California Department of Water Resources.

(Editor’s Note: Story by Robert Monroe, at UC San Diego Scripps Institution of Oceanography. The San Diego County Water Authority has partnered with the Scripps Institution of Oceanography at UC San Diego to better predict atmospheric rivers and improve water management before, during, and after those seasonal storms.)

California Snowlines On Track To Be 1,600 Feet Higher by Century’s End

This winter produced record snowfall in California, but a new study suggests the state should expect gradually declining snowpacks, even if punctuated with occasional epic snowfalls, in the future.

An analysis by Tamara Shulgina, Alexander Gershunov, and other climate scientists at UC San Diego’s Scripps Institution of Oceanography suggest that in the face of unabated global warming, the snowlines marking where rainfall turns to snow have been rising significantly over the past 70 years. Projections by the researchers suggest the trend will continue with snowlines rising hundreds of meters higher by the second half of this century.