Weekly update · December 27, 2023
El Niño Update, Week of December 27, 2023: Niño 3.4 at +2.0 °C
In the week of December 27, 2023, the sea surface temperature anomaly in the Niño 3.4 region — NOAA's main El Niño indicator — was +2.0 °C (28.6 °C actual), which corresponds to El Niño conditions.
Compared with the previous week it held steady, and over the last four weeks it held steady.
Off the coast of Peru and Ecuador (Niño 1+2) the anomaly was +0.8 °C (it fell 0.8 °C); this coastal warming is what most affects rain on the South American Pacific coast.
One year earlier, Niño 3.4 was at -0.7 °C.
| Region | Area | Anomaly | vs. last week |
|---|---|---|---|
| Niño 1+2 | coast of Peru and Ecuador | +0.8 °C | -0.80 |
| Niño 3 | eastern Pacific | +2.1 °C | 0.00 |
| Niño 3.4 | central Pacific (official index) | +2.0 °C | 0.00 |
| Niño 4 | western-central Pacific | +1.4 °C | 0.00 |
Niño 3.4, previous 52 weeks
← Dec 20Jan 3 →All weekly updatesEl Niño 2023Statistics
Frequently asked questions
Was there an El Niño in the week of December 27, 2023?
The weekly Niño 3.4 anomaly was +2.0 °C, above the +0.5 °C El Niño threshold. NOAA declares an event using the 3-month ONI and the atmospheric response.
Where do these numbers come from?
From NOAA's Climate Prediction Center weekly OISST v2.1 sea surface temperature data, published every Monday.
Source: NOAA CPC weekly OISST v2.1 (public domain). Generated automatically by El Niño Forecast; free to cite with a link.