El Niño 1997-1998
El Niño 1997-1998 lasted about 14 months, from Apr–Jun 1997 to Mar–May 1998. The Oceanic Niño Index peaked at +2.4 °C in NDJ 1997, a very strong El Niño, ranked #3 of 23 since 1950.
What happened
The "El Niño of the century": extreme rain and floods on the coasts of Ecuador and northern Peru, huge forest fires in Indonesia and the first global coral bleaching event on record.
Impacts vary by region and event; see our country pages for the usual pattern.
ONI before, during and after El Niño 1997-1998
Season by season
| Season | Year | ONI | Niño 3.4 temp. |
|---|---|---|---|
| AMJ Apr–Jun | 1997 | +0.7 °C | 28.44 °C |
| MJJ May–Jul | 1997 | +1.1 °C | 28.67 °C |
| JJA Jun–Aug | 1997 | +1.5 °C | 28.69 °C |
| JAS Jul–Sep | 1997 | +1.8 °C | 28.70 °C |
| ASO Aug–Oct | 1997 | +2.0 °C | 28.78 °C |
| SON Sep–Nov | 1997 | +2.2 °C | 28.92 °C |
| OND Oct–Dec | 1997 | +2.3 °C | 28.97 °C |
| NDJ Nov–Jan | 1997 | +2.4 °C | 28.96 °C |
| DJF Dec–Feb | 1998 | +2.2 °C | 28.85 °C |
| JFM Jan–Mar | 1998 | +1.9 °C | 28.76 °C |
| FMA Feb–Apr | 1998 | +1.4 °C | 28.64 °C |
| MAM Mar–May | 1998 | +1.0 °C | 28.63 °C |
Compare with other episodes
← El Niño 1994-1995El Niño 2002-2003 →La Niña 1995-1996La Niña 1998-2000El Niño 2026 (current)
Frequently asked questions
When did El Niño 1997-1998 start and end?
It started in AMJ 1997 and ended in MAM 1998, about 14 months.
How strong was El Niño 1997-1998?
Its peak ONI was +2.4 °C (NDJ 1997), classified as very strong. It ranks #3 among 23 El Niño episodes since 1950.
How does it compare with the current El Niño?
The current event (El Niño 2026) has reached +2.5 °C so far, above the +2.4 °C peak of El Niño 1997-1998.
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.