What exactly is the pineapple express??

Answer 1

Excellent question!! And one which is never fully explained on any weather forecast/ weather station....

Weather conditions are controlled by the air currents over the Pacific Ocean, for the most part, first of all. You can watch typhoons or Pacific hurricanes travel westward, until they reach a landmass, then these low-pressure storms will turn North-Northeast and follow the jet stream, until they are turned South-southeast ward, and affect the U.S. northwest states, Washington, Oregon, California.....

These extra-tropical storms keep their strength as they travel around the path of the Northern jetstream, droping rain and producing winds not unlike a hurricane, as they follow the jetstream paths around the world.

After these storms, these Pineapple Expresses, have traversed the United States, they again gain strength over the Northern Atlantic ocean, and then let go of the precipatation over Britian and Europe, where the Original storm dies.....

Again, excellent question. Hope this enlightens you!!

Answer 2

It's a weather system that comes in from Hawaii area to the west coast of Canada and US- usually brings a large amount of rain and warmer weather in the Northwest.

Stay dry!