1991-2020 Normals Dashboard - Nevada and Eastern Sierra

 

 

 

On October 1, 2021 the NRCS updated its 30-year normals period from 1981-2010 to 1991-2020. The NRCS uses normals in a variety of products to represent data as a percent of normal. Changing normals impacts percentages and requires users to re-calibrate themselves.

The following data types have normals:

• Daily and Monthly SNOTEL Snow Water & Accumulated Precipitation
• Peak SNOTEL Snow Water & Peak Date  (new)
• SNOTEL dates for Snow Onset &Melt-out (new) - click here for explanation
• Monthly Snow Course, Streamflow Volumes & Reservoir Storage

A Technical Summary about the new normals is available from the National Water and Climate Center.

Overview Presentation

The following video presentation highlights how the normals update impacts Nevada. For a pdf of the presentation slides click here.

Key Points about 1991-2020 Normals in Nevada:

• The median is the new default normal used in all NRCS products.
• Most 1991-2020 medians for snow, precipitation and streamflow in Nevada are less than 1981-2010 normals (exceptions exist).
• The main impact of a smaller normal is it produces a larger percentage.
• The reason 1991-2020 medians are less than the 1981-2010 normals is due to a combination of shifting the climate periods (1981-2010 to 1991-2020) and the statistical change from average to median.
• Streamflow forecasts have been re-calibrated with 1991-2020 data.
• New medians do NOT change SNOTEL data collection methods.

Tips for Adjusting to New 1991-2020 Medians

• Pay attention to how percentages are reported – median vs. average. External sources may mis-label data.
• Don’t expect as much water from a given percentage snowpack.
• Think like a water manager. Concentrate on streamflow volumes not on percentages.
• Investigate the new normals yourself using the tools lower on this page.
• Use tools that compare current data with historic years without percentages. Examples include:
  • Interactive SNOTEL Charts
  • Interactive Map -  SWE - Rank | Percentile | Records  Precipitation - Rank | Percentile | Records

Investigate the 1991-2020 Normals

Normals Technical Summary This Technical Summary of 1990-2020 Normals was produced by National Water and Climate Center and explains calculation methods and additional information.

Basin Snow Water Normals Comparison Select a Basin Chart LAKE TAHOETRUCKEE--Little Truckee--Sagehen-Independence--Galena--Steamboat Ck--Truckee ab Pyramid LakeCARSON--WF Carson--EF CarsonWALKER--West Walker--East WalkerNORTHERN GREAT BASIN--Surprise Valley - Warner Mtns--McDermitt Ck--QuinnUPPER HUMBOLDT--Marys--Lamoille Ck--NF Humboldt--SF HumboldtLOWER HUMBOLDT--Reese--Martin Ck--Little Humboldt--Humboldt R ab Imlay (Upper & Lower)CLOVER VALLEY & FRANKLIN R--Clover Valley--Franklin RSNAKE--Bruneau Headwaters--Jarbidge--Salmon Falls CkOWYHEE--Owyhee ab Owyhee--Owyhee ab Gold Ck--SF OwyheeEASTERN NEVADA--Steptoe ValleySPRING MTNS & SOUTHERN NV--White--Virgin--Upper ColoradoSTATE OF NEVADA & EASTERN SIERRAEASTERN SIERRA (Central Lahontan Basin) Basin charts combine data from multiple SNOTEL sites within and adjacent to a watershed. Drop downs use ALL CAPS for main basins, while Title Case is used for sub-basins.

Basin Precipitation Normals Comparison Select a Basin Chart LAKE TAHOETRUCKEE--Little Truckee--Sagehen-Independence--Galena--Steamboat Ck--Truckee ab Pyramid LakeCARSON--WF Carson--EF CarsonWALKER--West Walker--East WalkerNORTHERN GREAT BASIN--Surprise Valley - Warner Mtns--McDermitt Ck--QuinnUPPER HUMBOLDT--Marys--Lamoille Ck--NF Humboldt--SF HumboldtLOWER HUMBOLDT--Reese--Martin Ck--Little Humboldt--Humboldt R ab Imlay (Upper & Lower)CLOVER VALLEY & FRANKLIN R--Clover Valley--Franklin RSNAKE--Bruneau Headwaters--Jarbidge--Salmon Falls CkOWYHEE--Owyhee ab Owyhee--Owyhee ab Gold Ck--SF OwyheeEASTERN NEVADA--Steptoe ValleySPRING MTNS & SOUTHERN NV--White--Virgin--Upper ColoradoSTATE OF NEVADA & EASTERN SIERRAEASTERN SIERRA (Central Lahontan Basin) Basin charts combine data from multiple SNOTEL sites within and adjacent to a watershed. Drop downs use ALL CAPS for main basins, while Title Case is used for sub-basins.

SNOTEL Snow & Precipitation Normals Comparison Select a Basin Chart Bear Creek, NV (321)Berry Creek, NV (334)Big Bend, NV (336)Big Creek Sum, NV (337)Big Meadow, NV (340)Bird Creek, NV (1155)Blue Lakes, CA (356)Bristlecone Trail, NV (1111)Buckskin Lower, NV (373)Burnside Lake, CA (1051)Carson Pass, CA (1067)Cave Mountain, NV (1152)Corral Canyon, NV (417)Css Lab, CA (428)Diamond Peak, NV (443)Disaster Peak, NV (445)Dorsey Basin, NV (453)Draw Creek, NV (454)Dry Creek, NV (1243)Ebbetts Pass, CA (462)Echo Peak, CA (463)Fallen Leaf, CA (473)Fawn Creek, NV (476)Forestdale Creek, CA (1049)Fry Canyon, NV (1262)Golconda, NV (1195)Granite Peak, NV (498)Green Mountain, NV (503)Hagan's Meadow, CA (508)Heavenly Valley, CA (518)Hole-in-Mountain, NV (527)Horse Meadow, CA (1050)Independence Camp, CA (539)Independence Creek, CA (540)Independence Lake, CA (541)Jack Creek Upper, NV (548)Jacks Peak, NV (549)Kalamazoo, NV (1150)Lamance Creek, NV (569)Lamoille #3, NV (570)Laurel Draw, NV (573)Leavitt Lake, CA (574)Leavitt Meadows, CA (575)Lee Canyon, NV (1112)Lewis Peak, NV (1006)Little Valley, NV (1242)Lobdell Lake, CA (587)Marlette Lake, NV (615)Monitor Pass, CA (633)Mt Rose Ski Area, NV (652)Poison Flat, CA (697)Pole Canyon, NV (1244)Pole Creek R.S., NV (698)Porter Canyon, NV (2170)Rainbow Canyon, NV (1110)Rubicon #2, CA (724)Seventysix Creek, NV (746)Sheldon, NV (750)Sonora Pass, CA (771)Spratt Creek, CA (778)Palisades Tahoe, CA (784)Summit Lk, NV (1194)Summit Meadow, CA (1052)Tahoe City Cross, CA (809)Taylor Canyon, NV (811)Toe Jam, NV (1136)Truckee #2, CA (834)Vacarro Spring, NV (1137)Virginia Lakes Ridge, CA (846)Ward Creek #3, CA (848)Ward Mountain, NV (849)Wheeler Peak, NV (1147)

April-July Streamflow Normals Comparison   For help accessing historic time series and histogram plots click here.

Retrieve 1991-2020 Normals

Interactive Map:

Snow:  Today's Median / Average  |  April 1 Median / Average

Precipitation:  Today's Median / Average  |  Water Year Median / Average

Streamflow:  Seasonal (April - July)  Median / Average  |  Water Year (Oct-Sep)  Median / Average