El Niño strong
RONI of +1.69 ºC in the JAS 2026 season. NOAA calls it El Niño from +0.5 ºC.
Source: NOAA/CPC · RONI
El Niño · Equatorial Pacific
In the JAS 2026 season, the equatorial Pacific is in a El Niño strong phase. The peak of this event so far is +1.69 ºC: number 8 among the 23 El Niños since 1950. NOAA keeps the status: El Niño Advisory.
What matters now
RONI of +1.69 ºC in the JAS 2026 season. NOAA calls it El Niño from +0.5 ºC.
Source: NOAA/CPC · RONI
Niño 3.4 changed by +0.3 ºC in 4 weeks and is +3.4 ºC above normal.
Source: NOAA/CPC · weekly temperature
The Niño 1+2 region is +5.2 ºC above normal. It is where a coastal El Niño usually starts.
Source: NOAA/CPC · weekly temperature
NOAA's monthly bulletin cites a chance above 83% in this month's synopsis. See the original text below.
Source: NOAA/CPC · ENSO bulletin
Event strength
RONI is the water anomaly in the Niño 3.4 region, as a 3-month mean, with the ocean's overall warming removed. Event strength comes from the departure from normal. Below, how many earlier El Niños reached each band at their peak.
The bands are the usual ones to describe event strength; NOAA only defines the +0.5 ºC threshold. Events above 2 ºC are rare.
Official bulletin
The US Climate Prediction Center publishes once a month the alert status and a synopsis, with the chance that the event continues in the coming months.
Alert status
El Niño continues to strengthen, with a strong-to-very strong El Niño likely through January-March 2027 (remaining greater than an 83% chance).
Original NOAA text, in English.
Issued on October 8, 2026 · next edition on November 12, 2026
Read NOAA's original bulletin →Where the water is warm
El Niño does not warm the whole Pacific equally. Each Niño region has its own position and tells part of the story.
Historical series · RONI since 1950
RONI season by season since 1950: this event compared with the same season in other years and with the strongest El Niños of the past.
months since the start of the event
| # | Event | Peak | Strength | Seasons |
|---|---|---|---|---|
| 1 | 1982–83 | +2.40 ºC | Very strong | 13 |
| 2 | 1997–98 | +2.28 ºC | Very strong | 12 |
| 3 | 2015–16 | +2.25 ºC | Very strong | 14 |
| 4 | 1991–92 | +2.12 ºC | Very strong | 15 |
| 5 | 1965–66 | +1.99 ºC | Strong | 12 |
| 6 | 1972–73 | +1.97 ºC | Strong | 12 |
| 7 | 1957–58 | +1.89 ºC | Strong | 16 |
| 8 | 2026ongoing | +1.69 ºC | Strong | 3 |
Event: at least 5 consecutive seasons at +0.5 ºC or more (NOAA definition). The current event is listed even before it completes 5. Each line in the chart starts at the first season above +0.5 ºC.
Impacts in Brazil
In general, El Niño changes where it rains and where it is hot. The effects below are trends seen in past events (INPE/CPTEC and NOAA), not forecasts for any city. Next to each region, what the portal's data show right now.
What usually happens
Rain
Below-average rain, especially in the eastern Amazon and the north of the region. The dry season gets longer and stronger.
Heat
Higher temperatures, with hotter days and nights.
Rivers
Lower rivers in the dry season and more severe drought, with isolated riverside communities and difficult navigation.
Fire and air
Higher risk of fires and smoke in the dry season, worsening air quality and breathing problems.
It has happenedIn 2015–16 and 2023–24, Amazon rivers reached record lows, with severe drought and strong wildfires.
What the data show now
Rain in El Niño years
For each city, we compare each month's rain with the normal for the same month (1991–2020), only in months when RONI was at +0.5 ºC or more (El Niño) or at -0.5 ºC or less (La Niña).
How it works
We show official and model data as they arrive, with the source in each block. This site does not issue forecasts or official warnings.
Indices: NOAA/CPC, once a day. RONI and ONI come by season since 1950; Niño region temperature comes week by week since 1981.
Bulletin: the monthly synopsis from NOAA's Climate Prediction Center, checked every 6 hours, shown in NOAA's original English text.
Rain: ERA5 reanalysis (Copernicus) via Open-Meteo, for the 100 largest cities, from 1991 on.
Drought, fire and warnings: the same sources as the Drought, Fires and Storms sections.
It is a warming of the equatorial Pacific water, from the centre to the east, that changes atmospheric circulation and rain in many parts of the world. The opposite, with colder water, is La Niña.
For NOAA there is El Niño when the index is at +0.5 ºC or more and is expected to continue; the event is confirmed after 5 consecutive seasons.
ONI is the Niño 3.4 anomaly as a 3-month mean. Because the whole ocean is warmer due to climate change, NOAA moved to RONI, which removes that overall warming. That is why RONI is lower than ONI today.
The portal uses RONI as the main index and shows ONI beside it, for those comparing with older news.
Rain in El Niño months
Too few tracked cities in the region to compare.
What usually happens
Rain
Below-average rain in the north of the region and in the semi-arid area, mainly from February to May, the rainy season.
Heat
Above-average temperatures, with more very hot days.
Crops and water
Higher risk of drought and crop loss, with pressure on water for people and cattle.
It has happenedThe long 2012–2017 drought in the semi-arid area included the strong 2015–16 El Niño.
What the data show now
Rain in El Niño months
-9%against normal, averaged over the 3 tracked cities in the region.
What usually happens
Heat
Higher temperatures and more heat waves, especially in late winter and spring.
Rain
Irregular rain: more variation from place to place and a risk of dry spells in the middle of the rainy season.
Crops and water
Soy planting, from September to December, may suffer from irregular rain.
What the data show now
Rain in El Niño months
Too few tracked cities in the region to compare.
What usually happens
Heat
Higher temperatures, especially in winter and spring, and more heat waves.
Rain
Irregular rain, with storms and heavy rain concentrated in a few days.
It has happenedIn late 2023 and the 2024 summer, with a strong El Niño, several cities had heat waves with record temperatures.
What the data show now
Rain in El Niño months
-1%against normal, averaged over the 3 tracked cities in the region.
What usually happens
Rain
Above-average rain, mainly in winter and spring.
Rivers
Fuller rivers and a higher risk of floods, including in Rio Grande do Sul and Santa Catarina.
It has happenedMajor floods happened in strong El Niños, such as in 1983, 2015 and 2023.
What the data show now
Rain in El Niño months
Too few tracked cities in the region to compare.
Every El Niño is different, and the climate also depends on the Atlantic and other factors. The numbers for each region are from the moment and do not prove El Niño is the cause.
Rain since 1991 is loading gradually: 12 of 100 cities complete. The map appears once cities are ready.
ERA5 rain (~30 km reanalysis). Only cities with at least 12 months of each phase are included. With few events, a city's average may reflect one or two extreme years.
Fixed rules: phase and strength by RONI; a change of 0.3 ºC or more in 4 weeks in Niño 3.4; event rank among the five strongest since 1950; Niño 1+2 at 3 ºC or more; the alert status in NOAA's bulletin. We show at most four.
Notices are written by fixed rules, without artificial intelligence.
El Niño raises the chance of certain rain and heat patterns, but guarantees none. Each place's weather also depends on the Atlantic, the season and chance.
The strength of the event in the Pacific is not the strength of its effect in each city.
Follow Civil Defense warnings. Avoid flooded areas and slopes on heavy-rain days, and drink water during heat waves.