Tucson is slated to sizzle, with temperatures topping 110 degrees this weekend. But heat-stressed residents can find some relief in evergreen forests with wildflowers and a trickling stream just an hour’s drive from the city.

There — at Marshall Gulch in the Catalina Mountains more than a vertical mile above Tucson — temperatures can be at least 20 degrees cooler than on the desert floor.

Pine, fir and maple trees provide soothing shade in a picnic area in the gulch and along nearby trails, including a 3.7-mile loop route made up of the Marshall Gulch and Aspen trails.

Wildflowers, including huge white cow parsnip blooms and golden columbines, brighten a road leading from the mountain village of Summerhaven to the gulch. Those and other colorful flowers also show up along trails in the area.

A few trickling streams add to the cooling atmosphere.

Michael Stanley, manager of the Mount Lemmon Water District, noted that water was flowing this week — if only a few inches deep — in Carter Canyon and Upper Sabino Creek high in the Catalinas.

A faint flow and some small pools of water also persisted along the Marshall Gulch Trail.

To reach the gulch area, follow the Catalina Highway northeast of Tucson for about 25 miles to Summerhaven. Continue south out of Summerhaven for about a mile to a parking area in the gulch.

Contact reporter Doug Kreutz at dkreutz@tucson.com or at 573-4192. On Twitter: @DouglasKreutz