Snow and Water Levels-Snotel Locates the Goods

Snotel snow and water sensor maps for the western USAll outdoor enthusiasts are (or should be) interested in weather related information. Snotel weather sensor sites monitored by the National Water and Climate Center (United States Department of Agriculture, Nature Resources Conservation Service) provide an array of historical and current data for hundreds of sites in the western United States and Alaska.



Not only can you get a sense of the current temperatures in your favorite outdoor areas, but you can figure out where the powder is and compare this data to what ski areas and local water reports are claiming.

By clicking on the state of interest in the map or the pulldown menu, you will see all of the sites in that western state:

You can then select sensor locations surrounding your area of interest to see what the averages are for a particular area. As we understand it, the sensors are located in a particular drainage so the NWCC can obtain data that represents the whole area, NOT maximum snow or snow water equivalents. Ski areas generally tend to ‘highlight’ the maximum powder for obvious reasons. By checking out multiple sites surrounding an area, coupled with personal experience in the area on interest, you can get a fairly good idea of where you’d like to go to either take advantage of the snow depth or avoid it, depending on whether or not you are skiing/boarding, biking, backpacking, hiking, or planning for kayaking/rafting/fishing trips and water flows.

In this example we select Red Mountain Pass (site# 713) in the San Juans, not too far from Silverton Mountain, Telluride and Purgatory. It is also the headwaters for the Animas and Uncompahgre Rivers. Here is the sensor data page for Red Mountain Pass:


By selecting the ‘Daily/Last 7 Days’ in the ‘Snow Depth’ field you can get a quick glimpse of the past week and current condiitions:

You can see the change in the snow depth over each 24 hour period.

For more detail, by selecting ‘Hourly/Last 7 Days’, you’ll see exactly that, hourly data so you can watch a storm or melt rate as it develops (note this image is split to reduce size):



You can see that prior to the storm that started a 6pm last night, the snow actually melted down to 27″ and then snowed 5″, and settled 1″. Our experience has been that when ‘-99.9’ is shown, it typically is precipitating. This is a good thing/bad thing. When it’s snowing (good thing), you do not know the rate (bad thing) until there is a break in the snow or rain fall. The duration, coupled with past experience and viewing past history, can give you an idea of what is really happening. It is not unusual to see 6 to 12″ in the data and find 12 to 16″ in sheltered areas on Red Mountain pass. Combining this data with Avalanche Forecasting can give you a broader picture of the conditions.

Note you can also view Snotel data using Google Maps as one of the choices on the site.