Jeffrey Brauner of Baltimore saw a global satellite image and noticed a "line of clouds extending all the way from the East Coast, across the southern U.S. and Pacific ... to the Marshall Islands. Is that very unusual?" NWS science officer Steve Zubrick says it's not: "It's sometimes called the Pineapple Express. ... It's basically a plume of moisture flowing along with the jet stream. It can span thousands of miles" and sometimes transports heavy precipitation.