Dust storms are more difficult to classify than we thought, only a select few are issued as dust storm warnings because they need to meet certain criteria.
One could have many local storm reports but it is on a small-scale whereas a large-scale dust storm could have less reports.
"To classify the biggest, longest time duration, and largest areal coverage for dust storms is tough, and subjective," According to the National Weather Service.
Classification for dust storms depend on how much area it covers, visibility and distance traveled.
According to the National Weather Service, the amount of local dust storm reports was 60 this year. However, only 17 had dust storm warnings issued.
Out of the 17, 16 applied to our entire county warning area, which includes Southeast California.
"Defining one dust storm from another is tricky, especially if the same dust storm impacts multiple areas," According to the NWS.
When a warning is issued, visibility must be ¼ of a mile or less. Reports from the public, law enforcement and trained spotters help verify the visibility.
"The correlation between how severe a dust storm is compared with how many reports and the lowest visibility in a report is hard to connect," According to the NWS.
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