Scattered to numerous thunderstorms developed across south-central Arizona during the afternoon hours on August 2nd; many of the storms congealed into a large cluster of storms that moved slowly north and across Maricopa County into the evening hours. The storms generated strong and gusty outflow winds in excess of 60 mph that created widespread dust storms across the lower deserts. One large haboob that moved into the greater Phoenix area was at least 70 miles across and 5000 feet deep. Over a period of several hours, dozens of reports of dense blowing dust were received from trained spotters as well as the public and many reports indicated visibility had dropped to near zero miles in dense blowing dust. Three large Dust Storm Warnings were issued as a result of the widespread dust storms. Fortunately, no accidents or injuries were reported due to the very hazardous driving conditions that occurred as a result of the dense blowing dust.

Dust Storm in EAST VALLEY, ARIZONA
From 02-AUG-18 17:40:00 to 02-AUG-18 20:00:00 (MST-7)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

A large cluster of thunderstorms developed to the south of Phoenix during the afternoon hours and moved north and into the southeast portions of the Phoenix metropolitan area by early evening. The stronger storms generated strong gusty outflow winds in excess of 50 mph which stirred up massive amounts of dust and created a large haboob, or dust storm, that moved into the east valley lowering visibility to near zero miles. The haboob was said to be nearly 70 miles wide and 5000 feet deep at its peak. The dust storm impacted several east valley communities, including Chandler, Gilbert, Tempe and Mesa. Between roughly 1800MST and 1900MST over one dozen reports from around the east valley were received describing dust storm conditions. Reports were taken from trained spotters, the public, and NWS employees. Many of the reports indicated visibility lowered to below 250 feet and even down to near zero miles. Two Dust Storm Warning were issued back to back and were in effect at the time of the haboob. Fortunately, no accident or injuries were reported despite severely restricted visibility during the tail end of the rush hour.

Dust Storm in FOUNTAIN HILLS/EAST MESA, ARIZONA
From 02-AUG-18 18:30:00 to 02-AUG-18 20:00:00 (MST-7)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Scattered thunderstorms developed to the south of Phoenix during the afternoon hours on August 2nd; some of the stronger storms generated gusty outflow winds in excess of 50 mph that stirred up large amounts of dust and subsequently created dust storm conditions. During the early evening, a large dust storm moved north and through the east valley, including the area around Fountain Hills and East Mesa. At 1840MST a trained spotter located about 4 miles southwest of Apache Junction and near the intersection of the Superstition Freeway and Ellsworth Road reported a dust storm with visibility down below 200 feet in dense blowing dust. At 1902MST another nearby trained spotter 3 miles west of Apache Junction reported visibility below one quarter of a mile in a dust storm.  A Dust Storm Warning had been issued for the area at 1828MST and it remained in effect through 2000MST. No accidents were reported due to severely restricted visibility.

Dust Storm in SOUTH MOUNTAIN/AHWATUKEE, ARIZONA
From 02-AUG-18 17:40:00 to 02-AUG-18 18:45:00 (MST-7)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

A cluster of strong thunderstorms developed to the south of Phoenix during the afternoon hours and moved north and into the central portions of Phoenix area by early evening. The storms were accompanied by gusty outflow winds in excess of 60 mph which generated a massive haboob, or dust storm, that moved into the Phoenix area lowering visibility well below one quarter of a mile. At 1824MST, a trained spotter located 4 miles to the east of Ahwatukee Foothills reported visibility less than one quarter of a mile and dropping in the dust storm. A Dust Storm Warning was in effect for the area at the time. No accidents were reported due to the severely restricted visibility.

Dust Storm in BUCKEYE/AVONDALE, ARIZONA
From 02-AUG-18 18:25:00 to 02-AUG-18 20:00:00 (MST-7)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

A cluster of strong thunderstorms moved north across the western portion of the greater Phoenix area, including communities of Buckeye and Goodyear, during the evening hours on August 2nd. The stronger storms produced gusty outflow winds over 60 mph which generated massive amounts of blowing dust and caused widespread dust storm conditions. At 1830MST a public report was received indicating that visibility had dropped to between 20 and 50 feet in dense blowing dust about 1 mile east of Goodyear. The dust storm was near the intersection of Yuma Road and Estrella Parkway. A Dust Storm Warning had been issued for the area at 1828MST and it remained in effect until 2000MST.

Dust Storm in NORTHWEST PINAL COUNTY, ARIZONA
From 02-AUG-18 17:15:00 to 02-AUG-18 18:45:00 (MST-7)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Strong thunderstorms developed over the deserts to the south of Phoenix during the afternoon hours on August 2nd and the stronger storms generated gusty outflow winds in excess of 50 mph. The strong winds stirred up massive amounts of dust which resulted in a dust storm that moved north through much of northern Pinal County through the early evening. Dust storm conditions, with visibility one quarter mile or below in blowing dust, were reported by trained spotters as well as automatic ASOS weather stations. At 1739MST a trained spotter 2 miles east of Casa Grande reported visibility down to 100 yards in a dust storm. At 1755MST The Ak Chin airport ASOS station reported one quarter of a mile in dense blowing dust. At 1820MST, a trained spotter 1 mile north of Florence reported one eighth of a mile visibility in a dust storm. Two Dust Storm Warnings were issued for the area, the first was issued at 1715MST and the second at 1739MST. The second warning expired at 1845MST. No accidents or injuries were reported due to the dust storm.

Dust Storm in NORTH PHOENIX/GLENDALE, ARIZONA
From 02-AUG-18 18:30:00 to 02-AUG-18 20:00:00 (MST-7)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

A cluster of strong thunderstorms moved north across the western portion of the greater Phoenix area, including communities of Glendale and Peoria, during the evening hours on August 2nd. The stronger storms produced gusty outflow winds over 60 mph which generated massive amounts of blowing dust and caused widespread dust storm conditions. At 1903 a trained spotter 2 miles southwest of Peoria reported that visibility had dropped to below one quarter of a mile in dense blowing dust. A Dust Storm Warning had been issued for the area at 1828MST and it remained in effect until 2000MST. No accidents were reported due to the dust storm conditions.

Dust Storm in APACHE JUNCTION/GOLD CANYON, ARIZONA
From 02-AUG-18 18:30:00 to 02-AUG-18 20:00:00 (MST-7)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Scattered thunderstorms developed to the south of Phoenix during the afternoon hours on August 2nd; some of the stronger storms generated gusty outflow winds in excess of 50 mph that stirred up large amounts of dust and subsequently created dust storm conditions. During the early evening, a large dust storm moved north and through the east valley, including the town of Apache Junction. At 1847MST a trained spotter located about 2 miles southeast of Apache Junction and near the intersection of the Superstition Freeway and Tomahawk Road reported a dust storm with visibility below one quarter of a mile in blowing dust. A Dust Storm Warning had been issued for the area at 1828MST and it remained in effect through 2000MST.

Dust Storm in SOUTHEAST VALLEY/QUEEN CREEK, ARIZONA
From 02-AUG-18 17:40:00 to 02-AUG-18 18:45:00 (MST-7)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

A large cluster of thunderstorms developed to the south of Phoenix during the afternoon hours and moved north and into the southeast portions of the Phoenix area by early evening. The stronger storms produced gusty outflow winds in excess of 60 mph; these winds stirred up massive amounts of dust which resulted in a significant haboob, or dust storm, that moved through the area. Shortly after 1800MST, several reports were received of dense blowing dust with visibility below one quarter mile and down to near zero miles at times. At 1817MST a trained spotter 4 miles west of Queen Creek reported visibility down to one quarter of a mile or less in dense blowing dust. At 1822MST a public report was received of visibility down to about 100 feet in a dust storm near the intersection of Riggs Road and Gilbert road a bit to the east of Sun Lakes. Also, at 1827MST the Phoenix Mesa-Gateway airport ASOS measured visibility down to one eighth of a mile in dense blowing dust. A Dust Storm Warning was in effect for the area at the time. No accidents were reported due to the dense blowing dust and severely restricted visibility.