A large area of low pressure over the desert southwest led to strong and gusty southwest to west winds during the afternoon hours on April 12th. Gusts that exceeded 40 mph at times resulted in areas of dense blowing dust that affected portions of the greater Phoenix metropolitan area; trained spotters as well as Department of Highways personnel reported visibility lowered to one quarter of a mile in a dust storm in the early afternoon hours. No thunderstorms were present at the time, the gusts were generated due to strong low level winds associated with the large low pressure system. Numerous products were issued during the day including Wind Advisories, Blowing Dust Advisories and Dust Storm Warnings.

Dust Storm in NORTHWEST PINAL COUNTY, ARIZONA
From 12-APR-18 12:00:00 to 12-APR-18 19:00:00 (MST-7)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Strong gusty southwest to west winds developed over northwest Pinal County during the afternoon hours associated with a large area of low pressure that had developed over the desert southwest. Wind gusts that exceeded 40 mph at times created areas of dense blowing dust, lowering visibilities to one quarter mile or below and causing dust storm conditions for much of the afternoon. At 1552MST local law enforcement indicated that Interstate 10 near Casa Grande had been closed in both directions from milepost 191 to 194 for over 2 hours due to very poor visibility in dense blowing dust. Additionally, at 1523MST Department of Highways spokesman indicated that Highway 347 was closed for over three and one half hours between Interstate 10 and Casa Blanca Road due to low visibility from blowing dust. Initially a Blowing Dust Advisory was issued for the area, but it was upgraded to a Dust Storm Warning at 1349MST and the warning remained in effect until 1900MST. Fortunately, no serious accidents were reported due to the dense blowing dust.

Dust Storm in EAST VALLEY, ARIZONA
From 12-APR-18 13:00:00 to 12-APR-18 15:00:00 (MST-7)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Strong gusty west winds developed across the greater Phoenix area during the early afternoon hours on April 12, associated with a large area of low pressure that had developed across the desert southwest. Gusts over 40 mph produced areas of dense blowing dust that lowered visibility down to one quarter of a mile across portions of the east valley. At 1305MST, a trained spotter 2 miles southwest of Chandler reported one quarter mile visibility in a dust storm. Additionally, at 1300MST a Department of Highways employee indicated that visibility had lowered to one quarter of a mile in dense blowing dust. The low visibility was could be seen in an ADOT webcam. No accidents were reported due to the dense blowing dust. A Dust Storm Warning was issued due to the low visibility; it was initially issued at 1334MST and was cancelled at about 1500MST. In related but unfortunate news, a young Mesa father died of Valley Fever that he contracted while caught in the dust storm. He was working outside and got caught in the dust storm; he breathed in the spores and the subsequent fungal lung infection led to his death on June 2. He developed symptoms on May 20 and died 2 weeks later. The family moved to the area in April and he became sick shortly after he was hired. He left behind a wife and a young son.