Flash Flooding and Flood in Arizona, September 8 to 10, 2014

Widespread showers and embedded thunderstorms developed across the greater Phoenix metropolitan area during the early morning hours on September 8th. Although the thunderstorms were rather isolated, at 0200MST lightning from one of the storms struck a house in south Phoenix. The house was located near 27th Avenue and Baseline Road, at 9624 S 26th Lane in Phoenix. Neighbors reported hearing a large boom at 0200MST when the lightning bolt struck; by the time firefighters arrived the flames were too intense and they were forced to go into a defensive mode. Four children and two adults made it out of the house safely, however the house was a total loss.

Widespread and intense showers and thunderstorms developed across the central portions of the greater Phoenix metropolitan area during the early morning hours on September 8th; peak rainfall rates were well in excess of 2 inches per hour. The heavy rain led to significant urban flooding as well as flash flooding which affected the area around South Mountain, including the community of Laveen. Between 2 and 4 inches of rain fell during the morning, resulting flash flooding which damaged a number of homes; one of the zones hit hardest included residents along Dobbins Road between 19th Avenue and 51st Avenue. Many of the homes in the flooded area experienced similar flooding back on August 12th when 3 inches of rain quickly fell in the area. According to an article posted on-line at the Arizona Republic website, flood waters seriously damaged the home of Daniel Magos, located at 23rd Avenue and Dobbins Road. Flood waters also inundated the home of Augustin Ramirez in Laveen, located next to a cotton farm at the corner of Sunrise Drive and 51st Avenue. He had spent 20 thousand dollars repairing flood damage from back in August; the current flooding destroyed everything, including his recent renovations. Flood waters also inundated the home of Nick Kriaris, located at 19th Avenue and Dobbins Road. Water filled up the living room knee-high, causing him to lose everything. The washes coming down from South Mountain have been directed into the area, partly due to the construction of new subdivisions such as Woodside Homes. Poor drainage in the area also contributed to the significant flooding.

Widespread showers and embedded thunderstorms quickly developed across the entire greater Phoenix metropolitan area during the early morning hours on September 8th, and they produced very heavy rainfall with peak rain rates from two to nearly 6 inches at times. The heavy rain led to widespread urban flooding as well as episodes of flash flooding across the greater Phoenix area, resulting in numerous road closures. The road closures started shortly after 0230MST and became numerous by 0400MST. According to reports received via Twitter, State Route 51 flooded where the freeway dips below the Cactus Road underpass. Traffic in both directions was forced off the freeway, but allowed to re-enter both north and south of Cactus Road. The Superstition Freeway was flooded at Val Vista Drive with water up to the hoods of some vehicles, according to Public Information Officer Raul Garcia with the Arizona Department of Public Safety. The Loop 202 Santan Freeway was closed in both directions at the Loop 101 interchange. Interstate 17 southbound was closed from Grant to 19th Avenue due to flooding. Flooding also occurred on I-17 at Indian School Road, and at Greenway where the road below the freeway was flooded and closed. Interstate 10 was closed at the Riggs Road exits in both directions due to flooding. Finally, Interstate 10 was closed at 43rd Avenue due to flooding; at least 12 cars were stranded after water several feet deep covered the road and turned the interstate into a lake.

Widespread showers and embedded thunderstorms developed across the central portion of the greater Phoenix metropolitan area during the early morning hours, and they produced intense rainfall with peak rainfall rates well in excess of 2 inches per hour. The heavy rain continued into the middle of the morning before tapering off and resulted in significant urban street flooding, affecting motorists across the greater Phoenix area. At 0724MST a public report was received indicating that 4.39 inches of rain was measured 2 miles southwest of Ahwatukee. At about the same time, a trained spotter 3 miles southeast of Tempe measured 4.82 inches of rain since the rain began in the early morning. Finally, at 0633MST, another trained spotter 3 miles southwest of the Fiesta Mall in Mesa measured 4.08 inches of rain. The widespread street flooding caused many roads to become closed or restricted and created hazardous driving conditions during the morning rush hour across the greater Phoenix area.

Widespread showers and thunderstorms developed across the greater Phoenix metropolitan area during the early morning hours on September 8th, and they persisted into the early afternoon hours. Some of the heaviest rainfall fell in the central and southeast portions of the valley, in communities such as Tempe and Chandler. Peak rainfall rates were easily in excess of 2 inches per hour, and briefly spiked as high as 6 inches per hour. Many rain gages measured between 3 and 5 inches during this heavy rainfall event, and the heavy rain led to widespread and significant urban street flooding, as well as episodes of flash flooding. At 1138MST, a trained weather spotter 3 miles northwest of the Chandler Fashion Square Mall measured a storm total rainfall of 6.09 inches. A bit later, at 1349MST, another trained spotter 3 miles southeast of Tempe measured a storm total rainfall of 5.75 inches. The widespread street flooding created very hazardous driving conditions for Phoenix area motorists, especially during the morning rush hour. Many roads across the greater Phoenix area were either restricted or closed for several hours or more.

Widespread showers and embedded thunderstorms developed across the central and southeast portion of the greater Phoenix metropolitan area during the early morning hours on September 8th, and they persisted into the middle of the morning. The showers produced intense rainfall; gages indicated rain rates from 2 to nearly 6 inches per hour at times. Many locations across Tempe and Chandler received 2.5 to 5 inches of rain during the morning. According to an on-line article posted by the East Valley Tribune, at about 0800MST heavy rain caused the collapse of a roof at the Fry's grocery store located at the intersection of Baseline Road and McClintock Road. The Tempe Fire Department indicated that there were no injuries, and that the store would be closed until further notice.

Widespread and intense showers and embedded thunderstorms developed across the central portion of the greater Phoenix area during the early morning hours on September 8th, and they affected the community of Ahwatukee. Rainfall rates with the heavier storms exceeded 2 inches per hour at times and led to significant flooding of streams, washes and roads in the area, and the flooding seriously impacted the Mountain Park Community Church located at 24th Street and Pecos Road. A wash that runs behind the church crested during the morning's heavy rainfall and sent water cascading into the church. The water rose above the chairs in the auditorium, actually filling up the entire auditorium. The flooding made for a massive cleanup, and close to 75 volunteers rallied during the afternoon to clean up the mud and debris.

Showers and embedded thunderstorms produced very heavy rainfall in Mesa during the morning hours on September 8th; peak rain rates were well in excess of 2 inches per hour and many locations received between 3 and 5 inches of rain with this event. According to gage data from the Maricopa County Flood Control Network, some of the heaviest rain in the greater Phoenix area occurred in east Mesa during the early morning hours, with measured rainfall totals exceeding 5 inches within a 6 hour period. The heavy rain led to significant flash flooding across Mesa during the morning hours resulting in damage to area homes and businesses as well as severe disruption of morning traffic. One area that was especially hit hard was the Emerald Acres neighborhood located just north of US 60, and bounded by Stapley Drive and Harris. Due to various man-caused factors, the flash flooding was followed by areal flooding which persisted in the neighborhood for about 2 days and resulted in millions of dollars in damages to over 200 homes.

Widespread and intense showers...along with embedded thunderstorms...developed across much of the greater Phoenix metropolitan area, including southeastern valley communities such as Chandler and Tempe, during the early morning hours. Rainfall rates were well in excess of 2 inches per hour, briefly reaching to near 6 inches per hour, and the heavy rain led to significant urban as well as flash flooding. At about 0300MST a trained weather spotter reported serious flooding and hydroplaning occurring at the intersection of the Loop 101 northbound and Guadalupe Road in Tempe. Three of the lanes were flooded and impassable.

Widespread showers and embedded thunderstorms produced very heavy rainfall across the central portions of the greater Phoenix area during the early morning hours on September 8th. Rainfall rates were well in excess of 2 inches per hours at times, and the heavy rain caused major flash flooding on Interstate 10. At 0400MST the Arizona Department of Transportation reported that Interstate 10 was closed at 43rd Avenue, as the intense rain caused a lake to form several feet deep across the freeway. Since it was pitch black at the time, motorists unwittingly drove into the lake and became stalled; at least 2 dozen motorists became stranded in water which came up to the top of their hoods. The freeway was soon closed between 35th and 67th Avenues; after the water began receding at 0930MST, ADOT crews worked feverishly to clean up the road. Westbound Interstate 10 partially opened by 1400MST, the eastbound lanes were closed through the early evening hours.

Widespread showers and embedded thunderstorms developed across the greater Phoenix metropolitan area during the early morning hours, and they produced intense rainfall which affected the northern communities such as Carefree, Cave Creek and Anthem. Peak rainfall rates exceeded 3 inches per hour at times, and many trained weather spotters across the area measured between 2 and 5 inches of rain during the morning hours. At 0734MST, a trained spotter 5 miles southeast of Anthem reported flash flooding and indicated that the road was closed and impassable at the intersection of Cloud and Central. No injuries were reported due to the flash flooding.

Widespread showers and embedded thunderstorms produced very heavy rainfall in Mesa during the morning hours on September 8th; peak rain rates were well in excess of 2 inches per hour and many locations received between 3 and 5 inches of rain with this event. The heavy rain led to significant urban flooding across Mesa, and one area that was especially hit hard was the Emerald Acres neighborhood located just north of US 60, and bounded by Stapley Drive and Harris. Water flowing towards the south ran up against a large berm protecting the Superstition freeway and had nowhere to go. A flood control canal bordering the freeway as well as several water retention basins were in place to protect against flooding; due to the excessive volume of runoff they were overwhelmed and as a result the neighborhood became flooded with one to three feet of water. Approximately 200 homes suffered significant flood damage and many residents had to be evacuated. Many of the homes suffered ruined flooring as well as damaged drywall that needed to be replaced. Crews started pumping water out of the area with large machines on Tuesday, September 9th and by early morning Wednesday, most of the water was removed from the streets in the Harris/Stapley neighborhood. It was estimated that water would not be completely removed for a week.