PHOENIX - This year's Southwest monsoon season will be remembered for unusually intense storms that brought months' worth of rain in just one day.
Some areas in Arizona, Nevada and New Mexico received more rain in a day than in a typical season, the National Weather Service said. The rains caused flooding, sending water into homes and closing roads throughout the region.
The monsoon season typically spans from mid-June to the end of September and is characterized by thunderstorms that stir up dust storms or rain. Mark O'Malley, a National Weather Service meteorologist based in Phoenix, said monsoon season occurs when thunderstorms and moisture are stirred up by winds coming from Mexico. Once September ends, winds change direction and storms are likely tied to activity happening off the Pacific Ocean in the Northwest, O'Malley said.
This summer, Phoenix and its suburbs received more than twice the average rainfall. A majority of the storms occurred in August and September. According to meteorologists, a Sept. 8 storm that was made up of remnants from Hurricane Norbert in Mexico brought more than 3 inches of rain to Phoenix Sky Harbor International Airport in just seven hours. The area's normal seasonal total is 2.7 inches. Overall the area around the airport received 6.3 inches, making it the seventh wettest season on record.
Nancy Selover, Arizona's state climatologist, said the rain may have helped with short-term drought conditions by moistening soil and freshening groundwater.
"We had less than an inch going into the monsoon," Selover said Wednesday. "For the year, we're quite a bit ahead of where we expect to be by the end of the year."
Several parts of the state were pummeled in August and September with one-day episodes of rain, wind and sometimes hail. The ensuing flooding resulted in several dramatic water rescues and freeways becoming small lakes. Authorities in Tucson attributed two deaths on Sept. 8 to the weather. One woman drowned trying to cross a wash and another died after her car was submerged.
In Nevada, an area of small towns about 50 miles northeast of Las Vegas and an adjacent Indian reservation were swamped by storms on Sept. 8. Transportation officials said it could take up to two weeks and $2 million to repair a section of an interstate in southern Nevada that crumbled during intense flash flooding.
Meteorologist Andrew Gorelow said about 1.2 inches of rain fell at Las Vegas McCarran International Airport, making the season the 31st wettest for that area. The area saw 22 days of thunderstorms, tying a 1955 record.
In New Mexico, metropolitan Albuquerque saw its 14th wettest monsoon on record. More than 5.6 inches of rain fell at the Albuquerque Sunport, the National Weather Service said. A river flooded in Carlsbad last week, forcing the evacuation of about 110 homes.
In September, a storm caused by remnants of Hurricane Odile led to the death of an oil field worker near Loving.