Dust storm warning
A Dust Storm Warning (SAME code: DSW) is issued by the National Weather Service of the United States when blowing dust is expected to reduce visibility frequently to 1⁄4 mile (400 m) or less, generally with winds of 25 miles per hour (40 km/h) or more.
The following is an example Dust storm warning issued by the National Weather Service in Tucson Arizona.
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