The same storm system destined to become a dangerous blizzard over the PlainsThursday into Christmas Day has already claimed lives.The strengthening storm triggered gusty winds in the deserts of California andArizona Tuesday. Winds in some areas gusted past 50 mph, kicking up suddenclouds of dust.

One such dust storm blew across a portion of Interstate 10 in Arizona near CasaGrande, south of Phoenix. A chain reaction crash occurred Tuesday morning,involving at least 20 vehicles and killing three people, according toauthorities.

Wind at nearby Casa Grande Airport went from calm at 10:30 a.m. MST to gustingto 25 mph by 11:15 a.m. The winds were enough to kick up clouds of dust, whichblew across the busy highway.

The same storm is already producing heavy snow in the the mountains of the FourCorners region and will affect millions of people, not only as a blizzard onthe Plains, but also in the South and East in the form of ice, flooding andsevere thunderstorms.

Story by AccuWeather.com Expert Senior Meteorologist Alex Sosnowski