With the arrival of winter weather, anyone contemplating a road trip does so with trepidation.

You check a state's Department of Transportation road conditions map, but wonder how "partial" is "partially covered," or what "significantly" means. And "impassible?" Is that how your mom defines it, or your dad?

Weather forecasts provide data, but precious little proof of what lies ahead.

Thankfully, a growing network of webcams peer down on stretches of highways across the country, providing at least a glimpse into real conditions.

Planning a recent trip across South Dakota when a winter storm was bearing down, I called up webcams along I-90 in Sioux Falls, Mitchell, Chamberlain, Reliance, Murdo, Wall and Rapid City. I learned that we were wise to delay leaving, then could track where patches of snow-packed highway still could be found — or at least for the stretch visible on camera.

That sums up the caveat to this tool. Actually seeing the highway either can scare you off or can lull you into complacency. As with all driving, even in the finest weather, you can never be sure what's over the next hill.

But mostly, the webcams are helpful, because they contribute to your body of information.

To see which highways are smiling for the camera, visit the website www.safetravelusa.com, which aggregates 511 travel info in all 50 states, even Hawaii (if, I suppose, you're worried about onshore flooding).

Fair warning: You may become captivated with certain cams. Often, I click on the remote Slim Buttes (S.D.) camera, just because the scenery is so beautiful, and the road so inviting.