Pineapple Express: It’s Actually Very Scientific

A Pineapple Express is many things: the name of several cocktails. A potent strain of marijuana. A Seth Rogen and James Franco film. A miniature train tour at Dole’s Pineapple Plantation. And, most immediately relevant to us, a meteorological phenomenon notorious for bringing torrential rainfall to the Bay Area.

Not everyone has experienced the first four, but if you live in the Bay Area you’re likely intimate with the latter. “Pineapple Express” is the cute name meteorologists gave to the smaller versions of atmospheric rivers that generally flow from the Hawaiian Islands and extend somewhere along the Pacific coast — like the Bay Area.

According to a Scientific America article published during our last adventure riding the Pineapple Express, an atmospheric river is “a conveyor belt of vapor that extends thousands of miles from out at sea, carrying as much water as 15 Mississippi Rivers.” It arrives as a series of storms dumping inches of rain over a period of days or even weeks.

Michael D. Dettinger and B. Lynn Ingram

That constant battering of rain can and does often lead to flooding, even in a city of hills. San Francisco was built on creeks, marshes, and, as we expanded into the Bay, landfill. A significant amount of rain can bring those creeks roaring back to life. Find out if a hidden creek is swelling under your feet right this moment with the Oakland Museum of California’s topographic map from the 1890s.

See how your fellow San Franciscans are doing with hashtags: #CAwx (California Weather), #CAflood, #CAstorm

Below are some shots from the last time SF was blanketed by a conveyer belt of rain in January 2017.

From snow to rain ugh #sfrain #sfmom #sfkids

A photo posted by Stef Tousignant (@steftousignant) on

It’s all gravy, baby life’s lovely // Even when the grey rain clouds right above me A photo posted by Harrison Dahme (@isthebaron) on

High times #pineappleexpress #floodwatch #com #kentfield #marin #marinstockphoto

A photo posted by Hasan Sume (@marinstockphoto) on

Rainy day view of the #baybridge. #pineappleexpress

A photo posted by Corey Keller (@coreykeller510) on

Torrential rain in SF today. #sanfrancisco #rain #pineappleexpress

A photo posted by Jane Lurie (@janeluriephotography) on

Torrential rain in SF today. #sanfrancisco #rain #pineappleexpress

A photo posted by Jane Lurie (@janeluriephotography) on

This post originally appeared on on January 23, 2017.

  • March 22, 2018