Before setting off for Saguaro National Park, we shared our concerns about the rapid rise in the outside temperature. By 10 a.m., it was already 90 degrees and climbing. Cloud 9 was situated in a site without shade, adjacent to a concrete-block wall, meaning the air-conditioner would struggle to keep the inside temperature in the upper 80s. We took heat-mitigation measures, leaving the dogs in a darkened cabin with ample water and an oscillating fan. Because Saguaro is divided between eastern and western districts, we decided to visit the western district first and then return to Cloud 9 to check on the dogs before proceeding to the eastern district.

The park gets its name from the iconic saguaro, a large cactus that is native to the Sonoran Desert and that does not grow naturally elsewhere.

Saguaros grow very slowly at first—an inch or so during their first six to eight years. It may be 70 years before they sprout branches, or arms. They reach their full height of about 40 or 50 feet by age 150. The tallest can climb to 175 feet. Saguaros collect water through shallow roots extending about as far outward as the main trunk is tall. As they soak up water, they store it in the accordion-like spongy flesh in their trunks and arms. Although the plants produce edible flowers and fruits (the Tohono O’odham people make syrup, jelly and wine from the fruit pulp), the stored water is too acidic for quenching a desert thirst.

To access Saguaro West, we traveled through the 20,000-acre Tucson Mountain Park, one of the nation’s largest natural resource areas owned and managed by a county government. Although the park was established in 1929, the road through it began in 1883, when local rancher Thomas Gates wanted a quicker route to his carbonite mine in the Avra Valley. He paid $1,000 to clear and upgrade the winding road over the pass which now bears his name.

At the visitor center, we had the opportunity to interact with a friendly ranger who explained the reason for the warmer-than-usual temperatures. The recent monsoon season, one of the wettest on record with the area receiving as much rain in one month as it usually receives in a year, resulted not only in an off-cycle greening of vegetation but also higher-than-average humidity. That prompted us to remember our doggies, nestled in a 90-degree Cloud 9, so we hightailed it to our home on wheels to check on their well-being.

With outdoor temperatures in excess of 100 degrees, we decided to take the dogs with us on our motor tour of Saguaro East. The 8-mile scenic drive wound through a stand of saguaro forest set against the Rincon Mountains. This area of the park has been described as a “desert jungle,” due to the fact that it has so many species of plants and animals. We drove by saguaro forests, grasslands, and oak-pinyon-juniper woodlands, in addition to huge boulders and rock formations.

Upon returning to a very warm Cloud 9 (inside temperature holding at 90 degrees), we decided to change our itinerary and postpone our visit to Joshua Tree National Park until another, cooler time (daytime temperatures were forecast to be at or above 105 degrees for the next week). Consequently, we opted to visit higher-elevation Flagstaff and environs for a couple of extra days. With temperatures there ranging from lows in the upper 50s to highs in the mid-80s, and the opportunity to visit Walnut Canyon and Wupatki national monuments, it seemed like a worthwhile substitute.

Along the way, we learned some things worth sharing:

• GPS is wonderful technology (as we’ve noted before, it can actually save a marriage), so don’t even be tempted to look at the paper map provided by the friendly staff at the RV park.
• When climate change affects the “average” daily temperatures that you prepared for months earlier, don’t hesitate to head north to higher elevations, even it if means cancelling reservations and eating the subsequent penalties and fees.
• If you’re ever parked next to a concrete-block wall, remember, it can generate its own heat—lots of heat.