La Niña 2017-2018
La Niña 2017-2018 lasted about 7 months, from Oct–Dec 2017 to Feb–Apr 2018. The Oceanic Niño Index peaked at -0.8 °C in NDJ 2017, a weak La Niña, ranked #20 of 20 since 1950.
StartOND 2017Oct–Dec
EndFMA 2018Feb–Apr
Duration7 months5 seasons
Peak ONI-0.8 °CNDJ 2017
Average ONI-0.66 °Cduring the episode
StrengthWeak#20 / 20
ONI before, during and after La Niña 2017-2018
Season by season
| Season | Year | ONI | Niño 3.4 temp. |
|---|---|---|---|
| OND Oct–Dec | 2017 | -0.6 °C | 26.04 °C |
| NDJ Nov–Jan | 2017 | -0.8 °C | 25.80 °C |
| DJF Dec–Feb | 2018 | -0.7 °C | 25.83 °C |
| JFM Jan–Mar | 2018 | -0.7 °C | 26.11 °C |
| FMA Feb–Apr | 2018 | -0.6 °C | 26.68 °C |
Compare with other episodes
← La Niña 2011-2012La Niña 2020-2021 →El Niño 2014-2016El Niño 2018-2019El Niño 2026 (current)
Frequently asked questions
When did La Niña 2017-2018 start and end?
It started in OND 2017 and ended in FMA 2018, about 7 months.
How strong was La Niña 2017-2018?
Its peak ONI was -0.8 °C (NDJ 2017), classified as weak. It ranks #20 among 20 La Niña episodes since 1950.
Episodes are computed from NOAA's Oceanic Niño Index (ERSSTv5) with the standard rule: five or more consecutive overlapping seasons at or beyond ±0.5 °C. Free to cite with a link to elninoforecast.com.