Sometimes a picture is worth a thousand words, especially when you’re on a magazine deadline and time for blogging is short.
What you’re looking at is a massive dust storm—known in Arabic as a haboob—that enveloped much of Phoenix last night. Sand kicked up by strong downdrafts covered parts of the city, producing pictures like the one taken above by NOAA staff in the government agency’s Phoenix office.
Over on the WunderBlog, meteorologist Jeff Masters explained what happened:
Last night’s haboob was due to a large complex of thunderstorms known as a mesoscale convective system (MCS) that developed to the east of Phoenix. As the outflow from the MCS hit the ground, large quantities of sand and dust became suspended in the air by 50 – 60 mph winds. The amount of dust was much greater than is usual for one of these storms, due to the large size of the thunderstorm complex, and the extreme drought conditions the region has been experiencing. As the haboob hit Phoenix, winds gusted to 53 mph at Sky Harbor International Airport, and the airport was forced to shut down for 45 minutes due to visibilities that fell as low as 1/8 mile. The airport received only 0.04″ of rain from the storm, but large regions of Southern Arizona got 1 – 2 inches of rain overnight due to the monsoon thunderstorms.
The whole haboob was 50 miles long and 1 mile high. Oddly enough, the sand storm is actually a welcome sign for a region that has been gripped by extremely dry weather for months. The Southwest’s annual summer monsoon season is about to begin, and meteorologists are predicting significant rainfall over Arizona and western New Mexico, which have struggled with catastrophic wildfires. And just in case a picture’s not enough:
[youtube=http://www.youtube.com/watch?v=84ZZi75w0qk&feature=player_embedded]