“Pineapple Express”
Ashley Corrigan
SIO 209
January 25th, 2012
Pineapple Express:
Atmospheric River on West Coast
 Atmospheric rivers are “thin ribbons” of strong winds near
Earth’s surface that funnel moist, subtropical air over vast
stretches of ocean
 Pineapple Express: maritime term, referring to the fast
sailing time from Hawaii to Seattle due to these strong
surface winds
 Occur between October-April, with majority between January




February
Stream of moisture: 32°-52°N
Average about 2x as much precipitation as other, nonpineapple-express storms
Warmer minimum temperatures
Increases in streamflow that are an order of magnitude larger,
than other non-pineapple-express storms
From 1948-1999: 206 pineapple express systems
Michael Dettinger, “Fifty-Two years of Pineapple Express Storms across the West Coast of North America”
Average of 4 Pineapple Express
Systems per Year
Michael Dettinger, “Fifty-Two years of Pineapple Express Storms across the West Coast of North America”
http://en.wikipedia.org/wiki/Pineapple_Express
Detecting a Pineapple Express
“… distinctive jet-like
cloud paths (white
streaks) connecting
land-falling storms on
the West Coast to the
tropics near Hawaii”
Michael Dettinger, “Fifty-Two years of Pineapple Express Storms across the West Coast of North America”
Expensive Weather
Phenomenon
 Pineapple Express systems have caused nearly all of the largest
floods on record in California, resulting in nearly $400 million in
flood damage every year
http://cliffmass.blogspot.com/2010/09/incredible-humidity.html
Pineapple Express:
Jan 7th-11th, 2005
 Blocking High over
Aleutians resulted in
Low off the coast of
northern CA to become
stationary
 Allowed for prolonged
stream of subtropical
moisture to invade
southern CA
http://www.cnrfc.noaa.gov/storm_summaries/jan2005storms.php
Water Vapor
th
th
Jan 6 -12 , 2005
http://www.cnrfc.noaa.gov/images/storm_summaries/
jan2005/loops/satellite/wv/jan_wv_loop.php
Precipitation
01/10/2005
 Greatest 6-hour amounts
reached 4.37” at Nordhoff
Ridge in the mountains
near Ojai, CA
http://www.cnrfc.noaa.gov/storm_summaries/jan2005storms.php
Total Precipitation
Rain Gage
Precipitation
Jan 7-11. 2005
San Marcos Pass
24.64 in.
Nordhoff Ridge
27.99 in.
Opids Pass
31.94 in.
Palomar Mt.
12.67 in.
http://www.cnrfc.noaa.gov/storm_summaries/jan2005storms.php
Major Flooding in San Diego
http://photos.signonsandiego.com/050111storms
Major Flooding in North Co.
http://photos.signonsandiego.com/050111storms
Ephemeral Desert Lakes
 Desert locations received
as much as 9” of
precipitation, filling in
Badwater Basin
 Lowest point in North
America: 286m b.s.l.
La Conchita Landslide
 La Conchita community was
inundated by a landslide on
January 10th, 2005 due to
torrential rains from the 2005
Pineapple Express
 Bluff above La Conchita was
saturated with 14.9” of rain
received from Dec 27, 2004 –
January 10, 2005.
 Mean annual rainfall 15.4”
 Resulted in 10 fatalities and
destruction of 30 homes
http://www.laconchita.net/photos.htm