Thunderstorms developed across portions of the south-central deserts on July 14th. Some of the stronger storms generated typical monsoon weather hazards including very heavy rain - with peak rain rates in excess of 2 inches per hour - and damaging outflow winds. The intense rainfall led to a couple of episodes of flash flooding across the far western portion of the greater Phoenix area. The episodes included flooded and impassable roads as well as washes flowing swiftly and impacting road crossings. Additionally,  a storm over the far northern Phoenix area and about 5 miles west of Cave Creek produced damaging microburst winds over 60 mph that demolished a barn. No injuries were reported as a result of the flash flooding or strong winds.

Thunderstorm Wind in MARICOPA, ARIZONA
From 14-JUL-18 14:15:00 to 14-JUL-18 14:15:00 (MST-7)
Location: CAVE CREEK
Magnitude: 61.00 EG
Property damage: 50.00K
Crop damage: 0.00K
Reported by: Broadcast Media

Thunderstorms developed across the northern portion of the greater Phoenix area during the early afternoon hours; some of them affected the area around Cave Creek. The stronger storms generated gusty and damaging microburst winds. According to a report from local broadcast media, downburst winds estimated to be near 70 mph completely destroyed a barn about 5 miles west of Cave Creek. The barn was located to the south of Joy Ranch Road and north of Cloud Road, and just east of 7th Street. Several horses were injured in the process of the barn being destroyed. FAA radar indicated that surface winds in the area were in excess of 50 knots. There were no reported injuries to any humans, only to the horses.

Flash Flood in MARICOPA, ARIZONA
From 14-JUL-18 15:45:00 to 14-JUL-18 17:00:00 (MST-7)
Location: LIBERTY
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Thunderstorms developed over the southwest portions of the greater Phoenix area during the afternoon hours on July 14th. Some of the strongest storms produced intense rainfall with peak rain rates in excess of 2 inches per hour. The very heavy rain led to flash flooding in the Little Rainbow Valley, just northeast of the Maricopa Mountains. According to a trained spotter located about 14 miles southeast of the town of Buckeye, a storm produced 0.73 inches of rain within a 20 minute period ending at 1635MST. The intense rain caused Riggs Road and Rainbow Valley Road to become impassable. No Flash Flood Warning was issued, instead a Significant Weather Advisory was issued at 1547MST and it remained in effect through 1630MST.

Flash Flood in MARICOPA, ARIZONA
From 14-JUL-18 15:30:00 to 14-JUL-18 18:00:00 (MST-7)
Location: MORRISTOWN
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: River/Stream Gage

Thunderstorms developed across the northwestern portion of Maricopa County during the afternoon hours on July 14th and some of the stronger storms produced locally heavy rains with peak rain rates well above one inch per hour. The intense rains led to flash flooding in the Hassayampa drainage area, to the south of Wickenburg and southwest of Morristown. According to data from a Maricopa County Flood Control District streamgage along the Box Wash, located 9 miles southwest of Morristown, the wash rose 2 feet and impacted several road crossings including Whispering Ranch Road and Galvin Road. This occurred at about 1630MST. A Flash Flood Warning was issued for the area at 1530MST and eventually cancelled at 1736MST as floodwaters had significantly receded. No accidents or injuries were reported as a result of the flash flooding.