Although both seasonal and fleeting, snowpack is a valuable natural resource. The snow at Lassen Volcanic provides superb winter recreation and creates a winter habitat to which park animals and plants are well-adapted.
Lassen Peak Snowpack Measurements
Park staff began collecting measurements at the Lower Lassen Peak (LLP) snow course in 1930. Today, more than 50 state, national, and private agencies pool their efforts in collecting snow data throughout California. Visitors to the Lake Helen picnic area (8,250 feet elevation) may have spotted the 36-foot-tall snow sensor that collects and transmits real-time data to specialists at the California Department of Water Resources. Data from the Lower Lassen Peak remote station is manually verified four times each winter by a surveyor. View LLP sensor measurements (hourly/daily) or manual measurements (January - April) including manual measurement history since 1930.
2023 Lower Lassen Peak Manual Measurements
LLP Measurement Records
There are three main measurements for snowpack: depth and density, which combined determine snow water content equivalent. At Lassen, the records for each of these individual measurements occurred in April of different years.
The highest snow water content reflects the largest amount of water to result from snowmelt in the park in 1995, when the snowpack was both deep (287 inches/23.9 feet) and dense (51%).
How Much Water is in Snow?
Not all snow is equal when it comes to water content. Snow is composed of frozen water crystals, but because there is so much air surrounding each of those tiny crystals in the snowpack, most of the total volume of a snow layer is made up of air.
Forecasting Water from Snow
Data from the Lower Lassen Peak (LLP) snow measurement site is used to produce monthly forecasts from January to May. Forecasters use average density and depth for each snowpack to estimate spring and summer snowmelt runoff into rivers and reservoirs. Measurements taken on or around April 1 at established sites are generally the most significant as this is when the snowpack is normally at its greatest depth and density.
Lassen's Snowpack over Time
California Department of Water Resources has been recording snowpack measurements at Lower Lassen Peak since 1930. Data shows normal variations in snowpack over time. However, rapid changes in climate over the last few decades have resulted in warmer and drier conditions overall. Reduced snowpack leads to reductions in melted snow that is available to the state's water supply.
Last updated: May 7, 2023