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Snowpack at 114% After Weekend Storms Hit Rockies; Will We See a Repeat of Wet Winter?

It’s still more than seven weeks before the official start of winter (Dec. 21), but weekend storms in Colorado’s high country are reason enough to look in on snowpack levels that will eventually provide the water that flows to Lake Mead.

A month into the 2023 “water year,” snowpack levels are slightly above normal in the Upper Colorado River Basin: 114% as of Nov. 1, according to data on the U.S. Bureau of Reclamation’s website. The water year runs from Oct. 1 to Sept. 30 each year.

Summit Tackles Water Challenges Facing California

Below-average precipitation and snowpack during 2020-22 and depleted surface and groundwater supplies pushed California into a drought emergency that brought curtailment orders and calls for modernizing water rights.

Reviewing the Record-Breaking Water Year in Northern California

Sept. 30 marks the end of a water year to remember in California.

With the new water year kicking off Oct. 1, it’s worth looking back at the water year that was from record snowfall to landfalling tropical storms and everything in between.

California’s First Snow of Season is Coming to Sierra Ski Resorts

Less than two months since Mammoth Mountain’s historic ski season concluded, the first snowfall of the new season is set to arrive in the Sierra Nevada.

Weather models predict a low-pressure system with Canadian roots will bring cool temperatures and rain showers to the California coast and Central Valley on Saturday. In the Sierra Nevada, the air is expected to be cold enough for the first snowfall of the season at Kirkwood Mountain, Mammoth Mountain and other high-elevation ski resorts.

California Likely Spared Colorado River Cuts in 2024, but Long-Term Woes Remain

California will likely not face any cuts in Colorado River supply in 2024, according to a new forecast released on Tuesday by the U.S. Bureau of Reclamation. The agency said heavy snowpack and rains last winter mean planned reductions can be eased slightly from more urgent levels last year.

Inside a Plan to Completely Drain Lake Powell

Lake Powell will cease to exist if one group’s plan to restore Glen Canyon as the “heart of the Colorado River” comes to fruition.

An above-average snowfall and excessive precipitation in the spring have bolstered the water levels at Lake Powell and Lake Mead, but Glen Canyon Institute Executive Director Eric Balken told Newsweek that he doubts that Lake Mead will ever return to full capacity

Snowmelt Runoff Sets Streamflow Records in the Southwest

Across the western U.S., many areas received record or near-record amounts of snowpack over the winter. With the spring and summer temperatures melting the abundant snow, a record volume of streamflow has been recorded in several basins in the southwestern U.S., providing more water for the area later into the summer than is typically seen.

snowmelt runoff-streamflow-records

Snowmelt Runoff Sets Streamflow Records in the Southwest

Across the western U.S., many areas received record or near-record amounts of snowpack over the winter. With the spring and summer temperatures melting the abundant snow, a record volume of streamflow has been recorded in several basins in the southwestern U.S., providing more water for the area later into the summer than is typically seen.

Snowmelt runoff in Walker and Carson basins

The Walker and Carson basins near the California-Nevada border, for example, have reported the largest volume of streamflow for April through July that has ever been observed in roughly a century, when the records began. The ample runoff is helping fill reservoirs that have been depleted from years of drought conditions.

Weekly U.S. Drought Monitor: Cooler Northwest, Warmer Southwest

Dry conditions dominated the West and southern Plains, coupled with above-normal temperatures. Precipitation was most widespread throughout much of the upper Midwest and central Plains and into the Northeast. Almost the entire country had near- to above-normal temperatures this last week, with the greatest departures over the Southwest and central Plains where temperatures were at least 4-7 degrees above normal.

Cooler-than-normal temperatures were recorded in the Pacific Northwest with departures of 3-6 degrees below normal. At the end of the current U.S. Drought Monitor period, significant rains developed over portions of the Midwest and central Plains, and they will be accounted for in the next analysis.

U.S. Seasonal Drought Outlook

Central portions of the Intermountain West may be spared degradation, as those areas are still showing residual benefits from above normal winter snowpack leading up to the summer, in addition to periods of above normal rainfall during the last 60 to 90 days. Seasonal temperature and precipitation outlooks, ENSO, and climatology favor widespread drought improvement and removal across the central U.S. However, drought persistence is favored across the Upper Midwest, although there is the potential for localized improvements.” Read full assessment: cpc.ncep.noaa.gov/products/expert_assessment/sdo_summary.php.

Seasonal Precipitation Outlook: November, December, January 2023-24

Colors show where total precipitation has an increased chance of being higher or lower than usual during the next three months. The darker the shading, the greater the chance for the indicated condition. White areas have equal chances for precipitation totals that are below, near, or above the long-term average (median) for the next three months.

Climate scientists base future climate outlooks on current patterns in the ocean and atmosphere. They examine projections from climate and weather models and consider recent trends. They also check historical records to see how much precipitation fell when patterns were similar in the past.

Copernicus Climate Change Service: July 2023 sees multiple global temperature records broken

July 2023 highlights:

  • The global average temperature for July 2023 is confirmed to be the highest on record for any month.
  • Antarctic sea ice extent continued to break records for the time of year, with a monthly value 15% below average, by far the lowest July extent since satellite observations began.
  • July 2023 was wetter than average over most of northern Europe and in a region from the Black Sea and Ukraine to northwestern Russia. Drier than average conditions were experienced across the Mediterranean basin, with Italy and southeastern Europe having the largest anomalies.

July 2023 NOAA State of Climate Report

Record-high temps & devastating floods struck the U.S. 15 separate billion-dollar disasters occurred during the 1st 7 months of 2023. More from NOAA’s July State of Climate report.

(Editor’s Note: Content for this story comes from the Natural Resources Conservation Service, which produces a weekly report using data and products from the National Water and Climate Center and other agencies. The report focuses on seasonal snowpack, precipitation, temperature, and drought conditions in the United States.)

How Much Snow Still Covers California’s Mountains This July?

In a typical year, California mountains are largely snow-free at this stage in the summer, with some exceptions at higher elevations. This, however, has not been a typical year. In the last couple of weeks of July, large swaths of the Sierra continued to be covered in snow, making for tricky and in some cases treacherous hiking conditions.

Warming Causes More Extreme Rain, Not Snow, Over Mountains. Scientists Say That’s a Problem

warming world is transforming some major snowfalls into extreme rain over mountains instead, somehow worsening both dangerous flooding like the type that devastated Pakistan last year as well as long-term water shortages, a new study found.

Using rain and snow measurements since 1950 and computer simulations for future climate, scientists calculated that for every degree Fahrenheit the world warms, extreme rainfall at higher elevation increases by 8.3% (15% for every degree Celsius), according to a study in Wednesday’s journal Nature.

Heavy rain in mountains causes a lot more problems than big snow, including flooding, landslides and erosion, scientists said. And the rain isn’t conveniently stored away like snowpack that can recharge reservoirs in spring and summer.