http://en.wikipedia.org/wiki/Warm_front
http://en.wikipedia.org/wiki/Cold_front
http://windows2universe.org/earth/Atmosphere/tstorm/cold_front.html
http://en.wikipedia.org/wiki/Squall_line
http://en.wikipedia.org/wiki/Weather_front
http://www.wunderground.com/US/TX/Decatur.html
