Do Flash Floods Occur in the Desert?
Weather in the United States can change dramatically from season to season and from coast to coast. The country has a variety of different climates, from scorching hot deserts to blistering cold tundra. Surprisingly, climatic conditions can support flash floods in even the hottest desert regions.
Where are the four US deserts?
The US is home to a handful of deserts, where mild winters and exceedingly hot summers are the norm. The Mojave Desert extends through southeastern California, southern Nevada and southwestern Arizona. It is home to Death Valley, where temps can reach 134 degrees Fahrenheit.
The Sonoran Desert is further south, with rainfall between four and ten inches per year. Moist air blows in from the Gulf of California, creating mini summer monsoons. In summer, strong thunderstorms can pound heavy rains onto the desert ground.
Furthest south is the Chihuahuan Desert, where rain falls primarily in the summer. Rains between July and September come from the Gulf of California and can lead to flooding. The northern part of the desert undergoes winter rains, which are substantial enough to nourish springtime blooms.
The Great Basin Desert rounds out the four contiguous deserts in the US. As the northernmost desert, it spans over most of Nevada and western Utah. Here, the winters are primarily very cold. The Great Basin Desert also has the highest elevation, with precipitation varying by latitude.
What conditions cause flash floods?
Slow-moving thunderstorms, storms that immediately follow one after the other and heavy rains from tropical storms and hurricanes are responsible for flash floods. Within several minutes to a few hours of excessive rainfall, a flash flood will typically occur. Melting snow and ice can also cause flash flooding.
As heavy downpours persist, streams and dry riverbeds can quickly flood, especially if they are located in low-lying areas or steep terrain. Without vegetation to stop the flow of water, these dry riverbeds flood rapidly. Ground conditions also influence the potential for flash floods.
Extremely dry soil and clay soil, for instance, will prevent the ground from absorbing rainfall. As a result, the water remains above ground. Alternately, ground that is highly saturated with rainfall will force the rainwater to remain on the surface. Both circumstances can lead to flash flooding.
Certain environmental conditions can cause a surge of rapidly moving water that is loaded with large amounts of debris and sediment. For instance, high amounts of rainwater that fall into dry creeks, gullies, and rivers (or those that are flowing), can trigger flash flooding.
What causes flash floods in deserts?
Although the Sonoran and Mojave Deserts experience mild winters (with lows reaching 41 degrees Fahrenheit), the other two deserts are prone to freezing temperatures. The Chihuahuan Desert, for example, has lows that dip to freezing (32 degrees Fahrenheit) or a few degrees lower.
Desert streams that are laden with ice in winter will warm up in spring. Warm spring rains break up these ice sheets, and the large chunks of ice can form blockades. Behind the ice jam, water levels will rise. A sudden release of the water will cause flash flooding downstream.
In addition to flash floods produced by heavy spring rains falling onto melting snowpack, the exceedingly dry desert environments are ideal conditions for flash flooding. Desert sand fails to soak up rainwater quickly. Consequently, and without warning, heavy rains in these arid parts can lead to flash flooding.
The dry ditches, channels and lake beds of deserts are prone to violent surges of water when heavy rains pour. Walls of water 10 to 30 feet high are not uncommon. Desert thunderstorms are notorious for their unexpectedness, and they are strong enough to uproot trees and shift boulders.
All areas where rain falls are subject to flash flooding at any time of year. Deserts in the US, as mentioned, are not safe from the ongoing threats of flash flooding. Furthermore, flash flooding can occur without the typical warning signs, such as dark, rumbling clouds and heavy rains.
What are the best safety practices?
Flash floods are known to catch people by surprise. When traveling through the desert, stay informed throughout the trip. Sign up for weather alerts. Pay attention to lightning and thunder in the area. Be aware of flash flood locations, such as dry riverbeds, canyons, streams and low-lying areas.
When officials issue a flash flood warning, quickly move to higher ground. If in a car, drive to an area where flash floods are least likely, such as one 30 feet higher than the closest lowest point. Abandon the vehicle if the rains continue to rise up to the car.
Remember that a rainstorm can carry away cars, cause possible injury or fatalities and lead to costly damage to physical structures. Most often, rough storms are short-lived. When in the desert and anticipating rains, travelers are advised to get to higher ground and wait out the storm.
Get Help from ServiceMaster EMT
If you live in a desert area, water damage from flash floods is likely. Evacuate the home as a safety measure when flash flood warnings are issued. Once officials have given the clear to return home, it is important to restore your water-damaged property with help from ServiceMaster EMT.
Skilled water damage technicians from ServiceMaster EMT have advanced equipment and knowledge of the latest procedures to eliminate standing water from a home or business. Our water damage restoration process may be utilized for any sized structure with water damage.
Our comprehensive water damage restoration services include the extraction of excess moisture from the property, drying belongings, carpet and upholstery cleaning, dehumidification, and mold removal. We are available for emergency water damage cleanup services 24 hours a day, 365 days a year.
Residential homeowners and commercial business owners in all of Nevada and South California are encouraged to consult ServiceMaster EMT for the most dependable water damage restoration services.
Water damage spreads quickly, so call our professional crews at 800-376-6678 for an immediate response.