Disclaimer: The information below is intended to be used for gathering useful information for recreational purposes. The Natural Resources Conservation Service does not forecast avalanches, floods, or other hazards. The embedded links below are intended to assist you in finding relevant information from agencies that are tasked with these specific purposes.

Interactive Snow Water Equivalent (SWE) and Snow Depth     

Unlike snow depth, which can blank out during heavy snowfall events and settles between storms, SWE is a more stable metric of how much snow accumulated during a storm. It represents the amount of liquid water contained (or added) to the snowpack in inches, which translates directly into load applied to the snowpack. 

A good rule of thumb for estimating new snowfall from SWE accumulation at Montana SNOTEL sites is to assume a ratio of 10:1. That means if 1.0" of SWE is added to the snowpack, 10 inches of snow may have accumulated. "Cold Smoke," which is very low-density new snow (95% air, 5% water), equates to a 20:1 ratio. During the fall and spring months, when temperatures are typically warmer during storms, you might consider using a lower ratio of 8:1 or lower. 

The user controlled version of the map allows you to view the map in full-screen mode, select different metrics, change dates, etc. Try it out if you find the tools below don't fit your unique needs. 

(Select a Map Using Dropdown Below)

Current Avalanche Hazard

(Source: USFS National Avalanche Center)

7 Day Quantitative Precipitation Forecast

(Source: NOAA Weather Prediction Center)