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NOAA snow water equivalent

When the water equivalent of snow cannot be accurately measured by melting, weighing, or core sampling; the observer shall estimate the water equivalent to the nearest 0.01 inch. Use Figure 11-8, New Snowfall to Estimated Meltwater Conversion Table, only as a guide in estimating the water equivalency of newly fallen snow Station Snow Water Equivalent Reports Station Snowdepth Reports. Interpolated Snowfall Products. NOHRSC Mission Statement | Contact: National Weather Service National Operational Hydrologic Remote Sensing Center Office of Water Prediction 1735 Lake Drive W. Chanhassen, MN 55317: Contact NOHRSC Glossary Credit MIRS Snow Water Equivalent (SWE) Products. Click on a satellite name to view thumbnails. Click on a thumbnail to view full size. NOAA 20 +. SWE - Descending. SWE - Ascending. SWE Northern Hemisphere - Descending. SWE Northern Hemisphere - Ascending. SWE Southern Hemisphere - Descending NOAA - Modeled Snow Water Equivalent The National Operational Hydrologic Remote Sensing Center (NOHRSC) ingests daily ground-based (such as SNOTEL data), airborne, and satellite snow observations from all available electronic sources A network of Snow Telemetry sites—called SNOTEL—estimates snow water equivalent across basins by weighing the amount of snow that lands on pressure-sensitive snow pillows at stations across the west. Additional measurements come from automated stations and stations where people take manual measurements of snow. How do I use the site

The amount of water contained within the snow is called the snow-water equivalent. In just six weeks, California's snow-water equivalent totals have gone from below average to well above average — 186 percent of the February 21 average, in fact CNRFC - Hydrology - Snow Data. Snow Data. California Nevada River Forecast Center (CNRFC) Snow Water Equivalent / Snow Depth Summary - Interactive Map Interface. Daily Snow Water Equivalent Text Summary. Daily Snow Depth Text Summary. National Operational Hydrologic Remote Sensing Center (NOHRSC The snow water equivalent percent of normal represents the current snow water equivalent found at selected SNOTEL sites in or near the basin compared to the average value for those sites on this day. Data based on the first reading of the day (typically 00:00). Created Date

National Snow Analyses - NOHRSC - The ultimate source for

  1. Current Station Snow Conditions XML Permalink: Search by NWS ID: Data Filters. Elevation Range Amount; feet. feet. inches. inches. Map Overlays. NWRFC Boundary NWRFC Basins NWS HSAs Counties. Map Type. SWE Snow Status Snow % of Avg Seasonal Peak Status. Snow Density. Basin Obs Status Basin Sim Status Diff
  2. Snow Water Equivalent of Total Snow Depth Measure the water equivalent of ALL snow on the ground...old and new. The snow water equivalent is obtained by inverting the rain gauge can and pushing it through the entire depth of snow on the ground that represents the average snow depth
  3. This aircraft supports the National Weather Service's National Operational Hydrologic Remote Sensing Center (NOHRSC). NOHRSC has developed, and currently maintains, an operational Airborne Snow Survey Program to make airborne Snow Water Equivalent (SWE) and soil moisture measurements
  4. istration National Weather Service Alaska-Pacific RFC Alaska-Pacific River Forecast Center 6930 Sand Lake Road Anchorage, AK 99502 907-266-5160 Comments? Questions? Please Contact Us
  5. This data set contains snow pack properties, such as depth and snow water equivalent (SWE), from the NOAA National Weather Service's National Operational Hydrologic Remote Sensing Center (NOHRSC) SNOw Data Assimilation System (SNODAS). SNODAS is a modeling and data assimilation system developed by NOHRSC to provide the best possible estimates.
  6. Please note, the mapping interface and NWM products and web services are experimental. In addition to products from the NWM (streamflow, soil saturation), two products from the National Snow Analysis (snow depth, snow water equivalent) are available, as well as several useful reference maps from various sources
  7. Merging multiple data streams together can improve the overall length of record and achieve the number of observations required for robust statistical analysis. We merge complementary information from different data streams with a regression-based approach to estimate the 1 April snow water equivalent (SWE) volume over Sierra Nevada, USA

Snow Water Equivalent (MIRS) - Office of Satellite and

NOAA - Modeled Snow Water Equivalent NRCS Nevad

The NOHRSC snow model is an energy-and-mass-balance, spatially-uncoupled, vertically-distributed, multi-layer snow model run operationally at 1-km² spatial resolution and hourly temporal resolution for the nation. Ground-based and remotely-sensed snow observations are assimilated daily into the simulated snow-model state variables Snow Depth Change: 1 Day. 5 Day. 7 Day. 14 Day. Note: The water year starts on October 1 of the previous reference year and ends on September 30 of the reference year. For example, the 2020 Water Year began on October 1, 2019 and ended on September 30, 2020. National Weather Service California Nevada River Forecast Center 3310 El Camino. Near-to-above-average snow water equivalent was observed along the Sierras, the Great Basin, and central Rockies. During the course of the month, most of the region received an abundance of snowfall. By the end of February, snow water equivalent values of 125% to 200% of median could be found across most of the region. Below average values were.

Snow Water Equivalent in Western Basins - NOAA Climate

Table 1-2: Requirements for the NOAA GCOM-W1/AMSR2 snow water equivalent. EDR Attribute Threshold Objective Applicable conditions Delivered under all weather conditions Horizontal cell size 10 km 5 km Mapping uncertainty, 3 sigma 5 km 1 km Measurement range 10 - 200 mm Not Specified Measurement. Home > services > NWS_Observations > NOHRSC_Snow_Analysis (MapServer) > Snow Water Equivalent: Help | API Reference: JSON: Layer: Snow Water Equivalent (ID: 4) Sub Layers: Boundary; Footprint; Image; Name: Snow Water Equivalent Display Field: Type: Mosaic Layer Geometry Type: null Description:. snotel, snow water equivalent, GIS, snow course, maps, snow depth, snow densit

Snow Water Equivalent The water content obtained from melting accumulated snow. National Oceanic and Atmospheric Administration National Weather Service 1325 East West Highway Silver Spring, MD 20910 Page Author: NWS Internet Services Team: Disclaimer Information Quality Credits. The snow is then melted and measured as described above in the instructions for Snow Water Equivalent of Snowfall. From the perspective of water resources, flood prediction, and engineering, the most important observation (and one not taken by most weather observers) is the Snow Water Equivalent of Total Snow Depth

of snow-depth and water-equivalent measure­ mentsused. TABLE 1.-.Stations measuring both snow depth and water equivalent grouped by length of record Number of stations with data on: Years of re~ord used Snow depth Water equivalent 1-5 2 12 6-10 1 5 11-15 2 44 16-20 3 0 21-25 10 0 26-30 0 0 31-35 1 0 36-40 2 0 41-45 2 SNOTEL and Snow Course SWE, Snow Depth, and Snow Density; Graphs. SNOTEL Water Year Graphs - Current and average; SWE and precipitation; Snow Water Equivalent Update Graph - Horizontal bar graphs displaying % of average SWE Columbia River Snowpack Summary; Averages. Snow Water Equivalent 30-Year Averages (1981-2010 Snow depth (SNOWH, m) Snow layer liquid water (SNLIQ, mm) Snow water equivalent (SNEQV, kg m-2) Snowfall rate on the ground (QSNOW, mm s-1) Soil temperature (SOIL_T, K) Volumetric soil moisture, the dimensionless ratio of water volume (m3) to soil volume (m3) (SOIL_M, m3 m-3 0.00 (1981) 0.00. 1.70. 18.20 (2008) 30 Year Average: 1.70 inches. Latest Observation is 0.10 inches which is 6 % of average. Note: The Median/Average is based upon the 30 year period 1981 to 2010. The Min/Max is based upon the Period Of Record (POR). Data provided by the National Resource Conservation Service 0.20 (2003) 30 Year Average: 0.00 inches. Latest Observation: zero. Note: Statistics for Canadian stations are based upon the entire Period Of Record (POR). Data provided by British Columbia River Forecast Centre. Click For Data Used In Plots

SNOTEL Basin Time Series Snowpack Summary Graphs. Select options from drop-down menus or click watershed on map to view the line graph of the current water year. Format: Basin: Line Graph of SWE (inches) Line/Bar Graph of SWE as Pct of Avg Peak SWE Stacked Bar Graph of Monthly SWE as Pct of Avg Peak SWE Snow Water Equivalent Anomalies: GLB: NA: SA: AF: AS: AU: EU: US : NOAA/ National Weather Service NOAA Center for Weather and Climate Prediction Climate Prediction Center 5830 University Research Court College Park, Maryland 20740 Page Author: Climate Prediction Center Internet Team: Disclaime The current snow water equivalent percent of normal represents the snow water equivalent found at selected SNOTEL sites in or near the basin compared to the average value for those sites on this day. Data based on the first reading of the day (typically 00:00). Jul 11, 2021 Covers parameters such as ice water path (IWP), rain rate (RR), snow cover (SC) and snow water equivalent (SWE). To improve accuracy, visual inspections and verification of the various corrections are applied. The MHS sensor replaced AMSU-B on NOAA-15, 16, and 17 satellites Snow Water Equivalent (the amount of water content in a snowpack or snowfall). You can either type in the word you are looking for in the box below or browse by letter. Search

National Satellite Data CentreDrought Update for the Intermountain West | Drought

Snow Reports No non-zero station observations available. Note: these data are unofficial and provisional. Zip codes (where available) of observations will be included in text files after October 7, 2008. Station Snowfall Reports Station Snow Water Equivalent Reports Station Snowdepth Reports. Interpolated Snowfall Product Snow Depth Change: 1 Day. 5 Day. 7 Day. Daily Archive Note: The water year starts on October 1 of the previous reference year and ends on September 30 of the reference year. For example, the 2020 Water Year began on October 1, 2019 and ended on September 30, 2020. National Weather Service California Nevada River Forecast Center 3310 El. Water equivalent measurements are taken by extracting core samples, or slices, of the snow/ice on the ground, and then melting the sample to calculate the water equivalent of the snow/ice. The measurement can be done carefully with a rain gauge (e.g., an 8-inch sample of 16 inches on the ground melts to 1 inch of water, indicating an 8-1 ratio. According to NOAA data analyzed by the Rutgers Global Snow Lab, the March snow cover extent was 1.06 million square miles, 321,235 square miles above the 1981-2010 average.This was the sixth highest value in the 53-year satellite record. Above-average snow cover was observed across much of the West, Rockies, Great Plains, Midwest and Northeast. Below-average snow cover was observed in parts of. Connectivity between Eurasian snow cover extent and Canadian snow water equivalent and river discharge Stephen J. De´ry1 Program in Atmospheric and Oceanic Sciences, Princeton University, Princeton, New Jersey, USA Justin Sheffield and Eric F. Wood Department of Civil and Environmental Engineering, Princeton University, Princeton, New Jersey, US

This has left almost all of the Sierra Nevada weather stations below the 30th percentile of snow water equivalent, and a few locations in the Southern Sierra are even below the 10th percentile daily snow water equivalent summary srus56 krsa 141746 fstswe : : daily snow water equivalent summary : national weather service / california nevada rfc / sacramento ca : 1046 am pdt wed jul 14 2021 : : warning!! this product contains provisional data from automated gauges : this data has not been screened or verified for accuracy : this data. Soil Moisture & Snow Water Equivalent Evaporation & Runoff Precipitation & Temeperature Download Global Data U.S. Data U.S. GIS Data: About Us Our Mission Who We Are NOAA/ National Weather Service NOAA Center for Weather and Climate Prediction Climate Prediction Center 5830 University Research Court College Park, Maryland 2074

Snowpack + snowmelt = water National Oceanic and

In November 2014, NOAA aircraft flew missions over upstate New York after the record snow falls of up to seven feet and conducted airborne Snow Water Equivalent (SWE) and soil moisture measurements. Airborne SWE measurements are used by NOAA's National Weather Service when issuing river and flood forecasts, water supply forecasts, and spring. According to NOAA data analyzed by the Rutgers Global Snow Lab, the March snow cover extent was approximately 639,000 square miles, 101,544 square miles below the 1981-2010 average.This was the 18 th smallest value in the 54-year satellite record. Above-average snow cover was observed across much of the Northern Tier from Washington to the Great Lakes and into northern New England Alaska snow water equivalent percent of median map . See also: Alaska snow water equivalent values (inches) map . Water and Climate Update . 5/6/2021 Page 3 . Current Snow Depth, National Weather Service Snow Analysis ; Source: NOAA Office of Water Prediction; Water and Climate Update ; 5/6/2021 Page 4 ; Precipitation; Last 7 Days, NRCS SNOTEL. Note: Snow water equivalent is only one of the many variables that contribute to flood risk. Soil moisture conditions prior to freeze-up, frost depth, standing water levels in prairie potholes, rate of snow melt, spring rains, reservoir operations and other factors contribute to flood risk

This data set consists of a Northern Hemisphere subset of the Canadian Meteorological Centre (CMC) operational global daily snow depth analysis. Data include daily analyzed snow depths, as well as monthly means and climatologies of snow depth and estimated snow water equivalent (SWE) Snow geographic cover (and 2-layer snow water equivalent and snow temperature) is cycled in the Rapid Refresh on an ongoing basis, since 2011 at this point. The NESDIS IMS snow cover is used to horizontally trim and build snow cover, as described below. Use NESDIS IMS snow cover Applied to RAP at ~0z each day after new IMS snow data available

NRCS SNOTEL Snow Water Equivalent. Generate graphs that show cumulative snow water equivalent in river basins in western states of Alaska, Arizona, California, Colorado, Idaho, Montana, New Mexico, Nevada, Oregon, Utah, Washington, and Wyoming Explore NOAA // U.S. high-tide flooding breaks records. Sink your teeth into #SharkWeek. NOAA, Chicago partner on climate plan to reduce greenhouse gas emissions. Watch live: NOAA explorers help unlock mysteries of undersea mountains. 12 shark facts that just might surprise you

CNRFC - Hydrology - Snow Dat

Exceptionally early snow melt occurred in March over the northwestern Canadian Arctic and Alaska, contributing to below-average April snow water equivalent and snow depth. Earlier than normal snow melt also occurred across the eastern Canadian Arctic driven by warm temperature anomalies. Winter season snow accumulation was near normal over Eurasia Snow Water Equivalent Anomaly. Weekly: Monthly; 29Jun2021 - 06Jul2021 NOAA/ National Weather Service NOAA Center for Weather and Climate Prediction Climate Prediction Center 5830 University Research Court College Park, Maryland 20740 Page Author: Climate Prediction Center Internet Tea 3.1. Snow Water Equivalent Measurements [7] Available validation data for snow water equivalent is limited in terms of the length of record and area of coverage. In comparison to snow cover extent (SCE), which is generally measured at large scales via satellite remote sensing techniques, for example the IMS [Ramsay, 1998 Predefined Maps. To help you get started with the Interactive Map, here are links to predefined maps organized by data type. After opening a map, you can zoom to your area of interest, customize the map, and then bookmark the URL to save your settings. New features in this release Experimental Water Information Interface Webpage. The webpage can be found at https://water.noaa.gov/map. b. Purpose - The Experimental Water Information Interface Webpageis a mapping interface which allows users to display a range of water information, suchas snow depth; snow water equivalent; and NWM output

The operational products from F18 and F17 include: total precipitable water over ocean, cloud liquid water over ocean, rain water path, ice water path, rainfall rate, snow cover, sea ice concentration, snow water equivalent, land surface temperature, and surface emissivity over land and snow for all SSMIS channels Snow water equivalent of snowfall for the last 6 hours; Total snow depth; Snow water equivalent of total snow depth; Instructions on how to take the measurements are available here. To sign up as a CWOP snow data observer, please click here. To and enter CWOP snow data, please click here The National Water Model (NWM) is a new tool that simulates and forecasts how water moves throughout the nation's rivers and streams. Running on NOAA's powerful Cray XC40 supercomputer, the NWM uses data from more than 8,000 U.S. Geological Survey gauges to simulate conditions for 2.7 million locations in the contiguous United States NOAA anticipates any drought in the Northeast to end thanks to the expected weather patterns this spring. for the Upper Rio Grande most basins received a 15% boost in snow water equivalent

NERFC Snow Information Page. A snow lover needs to know three things: what is the snow forecast (col.3). This page provides all three in a simple clickable format. If there is something else you would like to see or a way we can make this page easier to use just drop us an email at... nerfc@noaa.gov. The six images at the top of the page all. North Dakota Risk Assessment MapService (NDRAM) allows users to zoom in and visually display current flood risks, both approximate floodplains from BLE and effective regulatory floodplains from FEMA's NFIP. This new tool also provides users water surface elevations, flood depths, and the ability to download engineering model data and print customized maps making it useful for planning. The Advanced Microwave Sounding Unit-B (AMSU-B) and Microwave Humidity Sounder (MHS) Brightness Temperature (BT) Climate Data Record (CDR) provides BT data from the window and water vapor channel frequencies of each instrument. Channels used are 89, 150, 157, 183 +/- 1, 183 +/- 3, 183 +/- 7, 190GHz. AMSU-B data comes from NOAA-15, -16, and -17 satellites, and MHS is from NOAA-18, -19 and MetOp-A Monday Night. Partly cloudy, with a low around 62. South wind 5 to 9 mph becoming north northwest in the evening. Tuesday. A 30 percent chance of showers and thunderstorms after noon. Mostly sunny, with a high near 92. Breezy. Tuesday Night. A 20 percent chance of showers and thunderstorms before midnight NOAA's Gulfstream Turbo (Jet Prop) Commander AC-695A, which primarily supports snow surveys, over Minnesota. NOAA's Gulfstream Turbo (Jet Prop) Commander is a high-wing, twin-engine turboprop that is suitable for a variety of missions. The aircraft plays a vital role in collecting data vital to flooding forecasts and water resource management

SCD anomalies (Fig. 2) were derived from the NOAA daily Interactive Multisensor Snow and Ice Mapping System (IMS) snow cover product (Helfrich et al., 2007).The IMS data are used to determine SCD due to the increased temporal and spatial resolution of the product. Snow cover onset (Fig. 2a) was normal to slightly earlier than normal over most of the Arctic Lastly the snow data is a part of the Snow dataset and includes snow depth and snow water equivalent. The HADS sites can change per owner operational needs. MADIS started ingesting SNOw TELemetry (SNOTEL) data directly from Natural Resources Conservation Service (NRCS) at the end of 2016. MesoWest was providing some SNOTEL data before this. This data set contains daily snow water equivalent maps over the central US. The maps were generated by NOAA/NOHRSC and its National Snow Analysis. This data set contains imagery from the two PLOWS field phases, 6 February to 30 March 2009 and 13 October 2009 to 10 March 2010. No imagery are available for the period between the field phases BE Maximum water equivalent since snow began to accumulate (in, mm) BF Areal water equivalent just prior to the new snowfall (in, mm) BG Areal extent of snow cover from the areal depletion curve just prior to the new snowfall (%) BH Amount of water equivalent above which 100 % areal snow cover temporarily exists (in, mm

Northwest River Forecast Center - Sno

Snow/sleet accumulation (in web product) - For NCEP RAP/HRRR forecasts until summer 2015, snow and sleet are combined into a single product called snow accumulation. This fixed-density snow accumulation is calculated using a 10:1 ratio from the accumulated snow water equivalent with both snow and graupel/sleet combined Snow Water Equivalent. Click on the graphic to the right to view snow water equivalent data from NOAA's National Operational Hydrologic Remote Sensing Center (NOHRSC) aggregated to Great Lakes basins. Click here to view gridded snow water equivalent from NOAA's National Operational Hydrologic Remote Sensing Center (NOHRSC). Ice Cove

This map displays current snow depth according to the National Oceanic and Atmospheric Administration (NOAA) National Snow Analyses (NSA). The NSA are based on modeled snow pack characteristics that are updated each day using all operationally available ground, airborne, and satellite observations of snow water equivalent, snow depth, and snow. - The Water Equivalent of Accumulated Snow Depth (WEASD) WMO headers were incorrectly labeled for forecast hours 186, 198, 210, 222 and 234. The following changes will be applied to each grid below: CONUS 20km: LSRU98 -> ZSNZ9

The snow water equivalent describes the amount of liquid water in the snow pack that would be formed if the snow pack was completely melted. A thematic accuracy of ~30-35 mm for conditions with less than 150 mm of SWE has been determined for the GlobSnow SWE product (Takala et al. 2011) 0%. Printable Version of Current Data. CDEC Stations included (Refer to the Page 6 report): NORTH: (Trinity through Feather & Truckee) ADM BFL BKL BLA BMW BNK CDP DSS FOR GOL GRZ HIG HMB IDC IDP INN KTL MB3 MED MUM PET PLP RRM RTL SCT. SDF SHM SLT SNM SQV STM TK2. CENTRAL: (Yuba & Tahoe through Merced & Walker

The snow is sticky due to its high partial liquid content. The ratio for wet snow will be less than 10:1. For example, a 5:1 ratio may occur in which it takes 5 inches of snow to produce 1 inch of liquid equivalent. DRY SNOW- A dry snow has little to no liquid water content thus this snow will be less dense than average Snow is an accumulation of packed ice crystals, and the condition of the snowpack determines a variety of qualities, such as color, temperature, and water equivalent. As weather conditions change, the snowpack can change as well, and this affects the characteristics of the snow. Snow most frequently appears white, but deep snow can act as a filter, absorbing more of one color and less of another

How to Take Snow Measurement

Snow Water Equivalent Clarification. Snowpack, quantified as snow water equivalent (SWE), is estimated as part of the Daymet processing in order to reduce biases in shortwave radiation estimates related to multiple reflections between the surface and atmosphere that are especially important when the surface is covered by snow (Thornton et al. According to department statistics, as of April 2, 2017, the snowpack's snow water equivalent (SWE) is 162 percent of the April 1 average, as compared to 84 percent of normal for the same date in 2016, and 5 percent of normal for the same date in 2015 A value of 253 is used to represent a no-snow/no-cloud data point. A value of 254 is used to represent a data point at which snow elevation could not be estimated because of clouds obscuring the remote sensor (when using aircraft or satellite measurements). (3) Snow water equivalent percent of normal is stored in percent of normal units Data and images displayed on STAR sites are provided for experimental use only and are not official operational NOAA products. More information>> JPSS/SNPP Data Product Operational Matrix. Sensor Data Product Priority ATBD S-NPP NOAA-20 Snow-Water Equivalent: 3: Provisional : GCOM-W: AMSR-2

50 Doomiest Graphs of 2010 – Desdemona DespairWater Year 2021: How Are We Doing?

Snow Water Equivalent & Soil Moisture Surveys - omao

  1. Figure noaa-led-state-summaries-2017 26.5: Variations in the April 1 snow water equivalent at the Noisy Basin, Montana, SNOTEL site. Snow water equivalent (SWE) is the amount of water contained within the snowpack. SWE varies widely from year to year. In 2011, late-season snowfall caused the snowpack to reach the greatest depths since 1975
  2. equivalent ratio (how fluffy the snow is). - Unrimed Dendritic and plate crystals have a lacy structures that usually produce the highest snow to liquid ratios (best accumulators) - The make-up of the cloud may affect the snow to liquid ratio. When there is abundant liquid water in cloud causing crystals t
  3. Evaluation of gridded snow water equivalent and satellite snow cover products for mountain basins in a hydrologic model. K. A. Dressler. Corresponding Author. The SCA product was the fraction of each 1 km 2 pixel covered by snow and was derived from NOAA advanced very high‐resolution radiometer imagery. The SWE product was developed by.
  4. conditions to the amount encountered under snow-covered conditions provides an estimate of snow-water equivalent (SWE). Field surveys have demonstrated the airborne gamma detection technique to be accurate to within 3.9% soil moisture (Jones and Carroll 1983), which amounts to less than 1 cm of snow-water equivalent
  5. The Environment Canada (EC) GCW Snow Water Equivalent Tracker provides an estimate of current Northern Hemisphere SWE relative to the 1998-2011 period. It is based on the Canadian Meteorological Centre operational daily snow depth analysis with SWE estimated using a density look-up table
Current ConditionsNOAA: Comparison Of The March 5th Snowpack Of 2018 vs 2017

Snow covered area and snow water equivalent are two essential measurements. Snow cover maps are produced routinely by the National Environmental Satellite Data and Information Service of the National Oceanic and Atmospheric Administration (NOAA/NESDIS) and by the US Air Force Global Weather Center (USAFGWC) The modeled snow water equivalent is verified with measurements. The resulting coefficient of determination between model and measurement is 0.62. The spatial performance of ESCIMO in the Weser catchment is validated by a comparison of the modeled with the snow cover derived from a NOAA-AVHRR image. The correspondence between the two images is. Snow water equivalent (SWE) at the majority of SNOTEL stations across the region peaked between 70-85% of the normal peak SWE this season. Early June SWE conditions are below to much below normal at most SNOTEL stations across the Colorado River Basin and Great Basin. Basins with the best remaining snowpack are the Uppe Snow water equivalent (SWE) values are derived from measurements taken at snow course and SNOTEL data stations. The amount of water contained in the snow columns are measured and expressed as percent of average and summarized by watershed. Snow water equivalent maps are available for the first of each month from January through June beginning.