CW3E Observations
Surface Meteorology
CW3E’s surface meteorological stations are located in watersheds across the western United States. These stations measure temperature, relative humidity, pressure, precipitation, wind speed and direction, and solar radiation. Most also measure soil moisture and temperature at six levels. Some stations include other quantities such as snow depth, fuel moisture, and temperature. Data are collected every two minutes and most stations are available in near real time. Efforts are ongoing to expand our observational networks and to make all observations available in near real time.
We would like to acknowledge our sponsors as well as our partners and collaborators that supported these instruments and allowed the deployment of these stations on their property. For more information about CW3E’s surface observations sponsors and collaborators, please see the bottom of the page.
Email alerts for extreme precipitation within the Yuba and Feather River watersheds are available for the CW3E deployed stations. For more information and to sign up for these alerts click here. An alert for CW3E stations and SNOTELS in and near the Upper Yampa watershed is also available. For more information and to sign up for these alerts click here.
An archive of CW3E collected surface meteorological and stream data in the Russian River watershed is available at https://doi.org/10.6075/J0SX6DDH.
CW3E data is also available on CDEC, MesoWest and NOAA’S PSL.
The plots here represent raw data from the station and have not undergone any quality control. Plots are updated once per hour. Please direct any questions and requests for past and/or QC’d data to cw3e-fieldwork-g@ucsd.edu.
Plot description: Surface meteorological and soil data observed at the location highlighted in the map. Top panel shows temperature (°F; blue line) and relative humidity (percentage; red line), second panel shows surface pressure (hPa; black line) and solar radiation (W/m2; green line), third panel shows wind speed (line; m/s) and direction (vectors), fourth panel shows hourly precipitation (inches; blue bars) and accumulated precipitation during the period shown (inches; red line), fifth panel shows the soil moisture (fraction) at various depths (color denoted by legend on right), and the bottom panel shows the soil temperature (°F) at the same depths as soil moisture. For an archive of raw data and images use FTP to connect to sioftp.ucsd.edu and navigate to /CW3E_DataShare/CW3E_SurfaceMetObs for data and /CW3E_DataShare/CW3E_SurfaceMetImages for images.
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Plot description: Accumulated precipitation (mm on left axis, inches on right axis) measured at the above the locations during the current water year (1 October – current day).
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MicroRain Radars
The vertically pointing MicroRain Radars (MRR) deployed by CW3E measure reflectivity and fall velocity up to 3000 meters above the instrument. Raw spectra are collected at 10 second intervals and the following plots, which also indicate freezing level and rain type, are updated at least once per day and up to once every hour, depending on station. The majority of our MRRs are co-located with disdrometers as well as surface meteorological stations.
We would like to acknowledge our sponsors as well as our partners and collaborators that supported these instruments and allowed the deployment of these stations on their property. For more information about CW3E’s surface observations sponsors and collaborators, please see the bottom of the page.
CW3E freezing level data calculated from the MRRs is also available on CDEC.
Plot description: The following plots show data collected from the MRR station highlighted on the map. The top panel shows reflectivity shaded by color and the bottom panel shows vertical velocity. MRR data are processed using an algorithm based on Maahn and Kollias 2012 but modified to improve the representation of heavy rain. Black circles represent the freezing level indicated by a radar bright band when bright band precipitation is present. The bar at the bottom of each chart shows the precipitation type (bright band:light gray, hybrid:medium gray, or non-bright band:dark gray) using an algorithm modified from White et al. 2003. Raw spectra measurements are collected every 10 seconds. Each plot shows the current day’s data, with time moving from left to right. Data is updated at least once per day and up to once every hour, depending on station. Time is in UTC. For more information on these radars click here. For an archive of processed 5 minute data and images use FTP to connect to sioftp.ucsd.edu and navigate to /CW3E_DataShare/CW3E_MRR.
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Disdrometers
The CW3E deployed disdrometers measure precipitation type, drop size distribution, intensity and velocity of all types of precipitation. Observations are collected every 10 seconds and the plots are updated hourly. The majority of our disdrometers are co-located with MRRs as well as surface meteorological stations. CW3E would like to thank our sponsors, collaborators and partners that enable the deployment of these instruments. A list of our sponsors and partners for disdrometers can be found under the MRR description.
CW3E precipitation type data calculated from the disdrometers is also available on CDEC.
Plot description: The plots below show data collected from a disdrometer deployed by CW3E at the location highlighted on the map. The top panel shows a scatter plot of rain intensity (mm/h) and the middle panel shows the radar reflectivity (dBZ). For the top two panels, the points are shaded according to the precipitation class determined by the disdrometer (see legend). The bottom panel shows the drop size distribution: the volume equivalent diameter (mm) is on the vertical axis, while each bin is shaded by the drop size frequency, which is expressed as a spectral number density (log scale). Measurements are recorded every 10 seconds. Each plot shows the current day’s data, updated once per hour, with time moving from left to right. Time is in UTC. For more information on these disdrometers click here. For an archive of processed 5 minute data and images use FTP to connect to sioftp.ucsd.edu and navigate to /CW3E_DataShare/CW3E_Disdrometer.
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We would like to acknowledge our sponsors as well as our partners and collaborators that supported these instruments and allowed the deployment of these stations on their property.
Surface Meteorological Stations
In support of Lake Mendocino Forecast Informed Reservoir Operations (FIRO), CW3E has been sponsored by US Army Corps of Engineers (USACE) Engineering and Development Center (ERDC) to operate several meteorological stations in the upper Russian River watershed in northern California in partnership with NOAA, Sonoma Water, UC Davis Bodega Marine Lab, Bureau of Land Management, Potter Valley Fire Department and local landowners.
Multiple meteorological stations have been installed in the Yuba-Feather watershed in northern California as part of the ongoing efforts of Yuba-Feather FIRO, sponsored by Yuba Water Agency, CA Department of Water Resources, and USACE, with close collaboration with NOAA, the Feather River College, San Francisco State University, California Nevada River Forecast Center, Browns Valley School, US Forest Service, Sierra Pacific Industries, and other local landowners.
In the Santa Ana watershed of southern California, efforts are underway to expand the current network in support of Prado FIRO, sponsored by USACE and in partnership with NOAA, U.S. Army Engineer Research and Development Center, and Orange County Water District.
CW3E was sponsored by NOAA’s Office of Weather and Air Quality to install meteorological stations in the Tuolumne watersheds to improve observations of high impact hydrometeorological events in the Sierra Nevada mountains of California. Ongoing maintenance of these sites and others that will be telemetered in the coming months, and installation of a new site in the Merced watershed is supported by the Department of Water Resources as part of CW3E’s Atmospheric River Program. These sites were possible with help from our partners at Hetch Hetchy Water & Power, San Francisco Public Utilities Commission, National Parks Service and Portland State University.
As part of ongoing efforts to develop the Yampa Basin Soil Moisture Network in northwestern Colorado, sponsored by the Upper Yampa Water Conservancy District, CW3E, in partnership with Colorado Mountain College, Yampa Valley Sustainability Council, the National Resource Conservation Service and private landowners, has installed one meteorological station with plans to further expand the network.
MRR and Disdrometers
We would like to acknowledge our partners and collaborators that help support these stations. CW3E’s stations in the Tuolumne-Merced watershed are sponsored by NOAA and California DWR and station location support from our partners at San Francisco Public Utilities Commission, National Parks Service and private landowners. In the Russian River, the stations are sponsored by USACE, and the sites were made possible through collaboration with Potter Valley Fire Department and UC Davis Bodega Marine Lab. The stations in the Yuba-Feather watershed are sponsored by DWR and Yuba Water Agency and sites were made possible through Yuba Water Agency and private landowners. In the Santa Ana watershed, CW3E stations are sponsored by USACE, and sites were made possible in collaboration with San Bernardino County Flood Control District and University of Southern California Wrigley Marine Science Center.