Header link June 22, 2020

LinkedIn

  • Read more
Header link September 15, 2014

Cart

  • Read more
Header link November 3, 2015

Donate Now

  • Read more
Header link May 15, 2014

Twitter

  • Read more
Header link May 15, 2014

Facebook

  • Read more
Header link May 15, 2014
Instagram

Instagram

  • Read more
Header link May 15, 2014

Contact Us

  • Read more
More options
Water Education Foundation
Home

Water Education Foundation

Everything about California water that matters
  • Water Academy
    • Agriculture
      • Agricultural Conservation
      • Agricultural Drainage
    • Background Information
      • Legislation — California and Federal
      • Regulations — California and Federal
      • Water History
      • Water Rights
    • Bay-Delta
      • Bay Delta
      • Bay Delta Conservation Plan
      • Delta Issues
      • Delta Smelt
      • Sacramento San Joaquin Delta
      • San Francisco Bay
      • Suisun Marsh
    • Dams, Reservoirs and Water Projects
      • California Aqueduct
      • Central Valley Project
      • Folsom Dam
      • Friant Dam
      • Hetch Hetchy
      • Hoover Dam
      • Infrastructure
      • Lake Mead
      • Lake Powell
      • Oroville Dam
      • San Luis Dam
      • Shasta Dam
      • State Water Project
    • Environmental Issues
      • Anadromous Fish Restoration
      • Ecosystem
      • Endangered Species Act
      • Invasive species
      • Lake Tahoe
      • Mono Lake
      • Public Trust Doctrine
      • Salmon
      • San Joaquin River Restoration
      • Watershed
      • Wetlands
    • Leaders and Experts
    • Regions
      • Central Coast
      • Central Valley
      • Mexico
      • Nevada
      • North Coast
      • Pyramid Lake
      • Sacramento Valley
      • Salton Sea
      • San Joaquin Valley
      • Sierra Nevada
      • Southern California
      • Tulare Lake Basin
    • Rivers
      • Carson River
      • Colorado River
      • Klamath River
      • New River
      • North Coast Rivers
      • Russian River
      • Sacramento River
      • Truckee River
      • San Joaquin River
    • Water Issues
      • Climate Change
      • Coronavirus
      • Drought
      • Earthquakes
      • Energy and Water
      • Floods
      • Fracking
      • Growth
      • Hydropower
      • Levees
      • Tribal Water Issues
      • Water Conservation
    • Water Quality
      • Drinking Water
      • Nitrate contamination
      • Pollution
      • Stormwater
      • Wastewater
      • Water Quality
    • Water Supply and Management
      • Acre Foot
      • Aquifers
      • California Water Plan
      • Conjunctive Use
      • Desalination
      • Grey water
      • Groundwater
      • Integrated Regional Water Management
      • Recreation
      • Surface Water
      • Water Marketing and Banking
      • Water Rates
      • Water Recycling
      • Water Supply
      • Water Transfers
  • Tours & Events
    • Water Tours
      • 2024 Tour Sponsors
    • Events
    • Event Calendar
    • Past Tours & Events
      • Anne J. Schneider Fund Lecture Series
  • Specialized Programs
    • Water Leaders
      • Cohort Rosters
      • Yearly Class Reports
      • Your Alumni Network
      • Alumni Profiles
    • Project WET
      • Workshops
      • Special Workshops & Events
      • Supplementary Materials
      • California Content Standard Correlations
      • Facilitator's Trainings
      • Foundation School Programs
        • Elementary Programs
        • Secondary Programs
      • Water Kids
      • California Project WET Gazette
      • Gazette Archives
    • Colorado River Project
    • GRA Scholastic Fund Program
  • Maps & Guides
    • Maps & Posters
    • Layperson's Guides
    • Map & Guide Bundles
    • Books
    • Colorado River Materials
    • California Runoff Rundown
    • Other Publications
    • Water Awareness Materials
    • Downloadable Publications
    • Videos and DVDs
      • Video Clips
    • School Age Publications
    • Stickers
    • Free Programs and Publications
  • Newsroom
    • Western Water News
    • Aquafornia
      • About Aquafornia
    • Information Desk
    • Western Water Magazine Archive
      • Full Print Edition
      • Print Edition Excerpts
    • River Report Archive
  • Aquapedia
    • Alphabetical List of Subjects
      • A
      • B
      • C
      • D
      • E
      • F
      • G
      • H
      • I
      • J
      • K
      • L
      • M
      • N
      • O
      • P
      • Q
      • R
      • S
      • T
      • U
      • V
      • W
      • X
      • Y
      • Z
    • Historical Water People
    • Where Does My Water Come From?
      • Northern California
      • Sacramento
      • North Bay
      • South Bay
      • Central Valley
      • Los Angeles
      • Inland Empire
      • San Diego
      • All California Water Sources
    • Timelines
    • Videos
    • Image Gallery
    • Water Directory
      • Federal Agencies
      • State Agencies in California
      • Environmental Organizations
      • Other California Organizations
      • State and Federal Legislative Committees
      • Water Associations and Groups
      • Western States Water Agencies and Districts
    • Online Resources
    • Useful Acronyms
    • About Aquapedia
  • About
    • About Us
      • Board of Directors
      • Staff Biographies
      • Job Openings
    • Announcements
    • Support Our Mission
      • Become a Member
      • Donate in Honor/Memory
      • Planned Giving
    • Contact Us
Aquapedia background September 10, 2014 Water Cycle Poster Layperson's Guide to Flood Management

El Niño/La Niña

California’s seasonal weather is influenced by El Niño and La Niña – temporary climatic conditions that, depending on their severity, make the weather wetter or drier than normal.

El Niño and La Niña episodes typically last 9 to 12 months, but some may last for years. While their frequency can be quite irregular, El Niño and La Niña events occur on average every two to seven years. Typically, El Niño occurs more frequently than La Niña, according to the National Oceanic and Atmospheric Administration (NOAA).

El Niño

Although El Niño conditions can bring above-average precipitation to California in the winter, that is not always the case. Strong El Niño years, however, tend to bring wetter conditions in Northern California, helping to replenish key reservoirs for the State Water Project and the Central Valley Project that serve much of the state’s urban and agricultural regions.

El Niño is characterized by unusually warm water temperatures in the Pacific Ocean at the equator. Its storm track affects the location of jet streams. Instead of coming ashore in the Pacific Northwest, the southern jet stream hits California with increased rainfall that is typically accompanied by floods, landslides and coastal erosion. El Niño tends to make atmospheric rivers stronger. El Niño events in 1982-1983 and 1997-1998 drenched the West Coast with record rain. The last El Niño, in 2018-2019, was weak. 

El Niño means “little boy” in Spanish, or in the context of Christmas, the Christ child, because of the time of year (around December) these warm-water events were historically observed off the coast of South America. El Niño is the warm phase of a larger phenomenon called the El Niño-Southern Oscillation, a periodic fluctuation in sea surface temperature and air pressure across the equatorial Pacific.

La Niña

La Niña, which means “little girl” in Spanish, is the opposite of El Niño, with a cooling of the ocean surface in the central and eastern tropical Pacific. La Niña winters typically result in dry conditions, particularly for Southern California.

La Niña results in colder ocean water off the West coast of the Americas, which pushes the jet stream north. In a La Niña winter, the storm track tends to hit the Pacific Northwest with heavier rain and flooding, sometimes dipping into Northern California. The American Southwest, meanwhile, is left drier than normal.

The colder water off the Pacific coast is more nutrient-rich and attracts more salmon, squid and other cold-water species to coastal California, according to NOAA.

Related Links

  • Print-friendly

Referring Pages

Share this page

  • Share on Facebook
  • Share on Twitter
  • Share on LinkedIn
  • Sent to a friend.
Print-friendly

Related Links

Aquapedia background September 10, 2014 Water Cycle Poster Layperson's Guide to Flood Management
Maps & Posters May 21, 2014

Water Cycle Poster

Water as a renewable resource is depicted in this 18×24 inch poster. Water is renewed again and again by the natural hydrologic cycle where water evaporates, transpires from plants, rises to form clouds, and returns to the earth as precipitation. Excellent for elementary school classroom use.

  • Read more
Publication May 20, 2014

Layperson’s Guide to Flood Management
Updated 2009

The 24-page Layperson’s Guide to Flood Management explains the physical flood control system, including levees; discusses previous flood events (including the 1997 flooding); explores issues of floodplain management and development; provides an overview of flood forecasting; and outlines ongoing flood control projects. 

  • Read more
Back
This item appears in:
  • Topic: Drought
  • E
  • Topic: Floods
Footer pod May 20, 2014

Water Education Foundation

Copyright © 2025 Water Education Foundation. All rights reserved.

The Water Education Foundation is a nonprofit, tax-exempt, 501(c)3 organization, federal tax ID #942419885.

Privacy Policy

Donor Privacy Policy

  • Read more
Footer pod May 20, 2014

Contact Information

2151 River Plaza Drive, Suite 205
Sacramento CA 95833

Telephone (916) 444-6240

Contact Us via email

  • Read more

Quicklinks

Footer quicklink May 20, 2014

Contact Us

  • Read more
Footer quicklink May 20, 2014

Donate Today

  • Read more
Footer quicklink May 20, 2014

Tours

  • Read more
Footer quicklink May 20, 2014

Newsletter Signup

  • Read more
Footer quicklink May 20, 2014

Foundation News

  • Read more
Footer quicklink May 20, 2014

Calendar

  • Read more

Commands

  • Support portal
  • Log in
 close

Log in

  • Create new account
  • Request new password