#LN0017-11 Winter 2017-18 Forecast: La Niña

According to the National Weather Service’s most recent forecasts, the U.S. is likely to experience a La Niña event this upcoming winter. El Niño and La Niña are opposite phases of the El Niño-Southern Oscillation (ENSO) cycle, which describes the fluctuations in temperature between the ocean and atmosphere in the eastern-central equatorial Pacific. A La Niña occurs when ocean temperatures in the eastern equatorial Pacific are colder than average. This leads to especially wet conditions in the northern U.S., and drier, warmer conditions in the southern U.S.

La Niña events usually last approximately 9-12 months, but some episodes may persist for as long as two or more years. In this case, it is predicted that La Niña will persist through the remainder of the year and into early 2018. This event is forecasted to be relatively weak and short-lived. Every La Niña is different and difficult to predict, so it is important that your site prepares for the rainy season as soon as possible. 

To prepare for a La Niña, general contractors and QSPs should perform the following:

  • Monitor daily weather reports for any incoming precipitation from NOAA
  • Implement and maintain best management practices according to your site’s SWPPP
  • Locate extra stock of BMPs onsite to deploy when needed – inquire about our Storm Kits
  • Schedule a SWPPPs refresher training session to review all protocols during a rain event
  • Ensure all sampling equipment are on hand and ready to use as necessary