Winter off-road driving has its advantages over the summer. There’s no 100-degree heat to worry about, no bugs, and potentially fewer people clogging up the trails. But snow depth is a real concern. The last thing you want is to load up your vehicle and find the snow is too deep to pass or you end up stuck.

The good news is you can get a pretty good idea of snow depth in the lower 48 by checking out the Sierra Snow Depth Map from the USDA Forest Service. Check out the map for yourself here.

Though the name implies you’ll only find information for California’s Sierra forests, a quick perusal reveals it has the same information for the vast majority of the United States and a good chunk of Canada. When you first click on the map, you are taken to the Pacific Southwest region, but you can move the map to any location you are considering traveling to.

The map shows you how much snow is on the ground all over the country and at all elevations. Map data comes from the National Oceanic and Atmospheric Administration (NOAA) National Snow Analysis (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 cover. The NSA are products of the National Operational Hydrologic Remote Sensing Center (NOHRSC),” according to the Map’s “About” section.

While it’s not a perfect tool, the Sierra Snow Depth Map will at least give you an idea of what to expect before you venture off-road. You can better plan your adventure by sticking to areas with lower levels of snow. Or, if you are feeling particularly adventurous, seek out areas with some powder to play in.

You can find a handful of other useful maps for off-roaders at the USDA’s Online Web Maps Gallery.