We drove through Yosemite a few weekends ago. It was packed with summer travelers and waterfall gawkers. The major falls are glorious, and fuller than they have been in years. New, smaller falls have even appeared much to the delight of park goers.

As we drove through the park, out past Mono Lake, we were stunned by the high water levels and snowy peaks in early July. We laughed, thinking that we could even cross-country ski in some spots above 7000 feet.

Record snowfalls this winter and heavy unseasonable rain in summer have made conditions epic for nature lovers but also hazardous.

Yosemite is drawing crowds, and visitors to the park should exercise caution while viewing the many falls and swollen creeks and rivers. Since June, there have been at least two people confirmed dead and two missing and presumed dead. The park has banned water rafting on the Merced River until the flows subside to their normal levels.

My son and a group of friends made the trek to Wapama Falls, a wonderful hike which wraps around the Hetch Hetchy reservoir. The photos were astounding, but just days later a Doctor and a friend, both experienced backpackers, were swept away by the torrents when crossing a small footbridge.  Sobering for the folks who took my son, who in hindsight, were fearful of the awesome cascade.

As we made our way back to the Sierras, we stayed at a friend’s house near Kirkwood Ski Resort. I took a short walk, alone, down to the “creek,” heretofore a tiny trickle, where as toddlers, my kids frolicked. At nearly 8,000 feet in elevation, the mule ears were just sprouting and snow patches still remained in early July. I decided to cross the creek and make a circle. Quickly I aborted my attempt. This repeated several times as the current was just too treacherous. I realized I was on my own and if swept away, it would not be a good scene.  I finally found a reasonable crossing point, and with numb legs and feet, made my way to the other side. Not only is the water higher, but it felt colder.

A recent article by Jane Brody in the New York Times Science section offers simple, but useful tips for both beach and mountain water fun. So get out and enjoy the majesty, but respect the elements and have caution!

Recently I joined a mini reunion of college pals in Sun Valley, Idaho for a trifecta of outdoor activities: mountain biking, fly-fishing, and river kayaking.

Read all about it in the San Francisco Chronicle travel section: Sun Valley’s Summer Rush.