[link|http://www.chron.com/cs/CDA/ssistory.mpl/front/1998508|Dust cloud in forecast for today]
A Saharan dust haze twice the size of Texas is expected to make its way over Houston today and cover the state by the weekend, health officials said Wednesday.
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The dust travels toward the United States from North Africa about four or five times between June and August each year, she said. Hurricanes and tropical storms also help pull the dust into the air over the Atlantic Ocean.