Oceans & climate / ENSO observatory
The Pacific’s changing state. Observations, seasonal forecasts and regional implications, with the evidence behind each number.
Checked 00:14 UTC. Source observation dates may differ.
El Niño continues to strengthen, with a strong-to-very strong El Niño likely through January-March 2027 (remaining greater than an 83% chance).
Next scheduled discussion: 12 November 2026. Original bulletin ↗
OBSERVATION / REGIONAL ANOMALY
+2.1°C
Above or below the seasonal average—not the water’s absolute temperature and not a global ocean average.
Reported in NOAA’s 8 October 2026 bulletin; not a daily measurement.
FORECAST / THREE-MONTH INDEX
83%
October–December 2026
Highest probability among the bulletin’s unexpired threshold periods. This is a forecast of index strength, not a probability of local impacts.
What about +4.00°C? NOAA reports anomalies exceeding that value in parts of the eastern equatorial Pacific. It is not a basin-wide average. The regional Niño-3.4 reading and the three-month relative index describe different measurements.
Sea-surface temperature anomalies reported in the bulletin, not observations taken at this page’s check time.
FORECAST / NOT OBSERVED TEMPERATURE
NOAA CPC · issued October 2026
The line is the median forecast RONI. Shading shows the central 50% and 90% forecast ranges for overlapping three-month seasons—not daily temperatures, and not the chance of impacts in your area.
Showing central 50% and 90% ranges
RONI · °C · baseline 1991–2020 · light band 90% · darker band 50%
| Season | 5% | 25% | Median | 75% | 95% |
|---|---|---|---|---|---|
| September–November 2026 | +2.18°C | +2.35°C | +2.47°C | +2.59°C | +2.76°C |
| October–December 2026 | +2.25°C | +2.54°C | +2.74°C | +2.94°C | +3.23°C |
| November 2026–January 2027 | +2.00°C | +2.39°C | +2.65°C | +2.92°C | +3.31°C |
| December 2026–February 2027 | +1.58°C | +2.04°C | +2.36°C | +2.68°C | +3.14°C |
| January–March 2027 | +1.13°C | +1.59°C | +1.90°C | +2.22°C | +2.67°C |
| February–April 2027 | +0.66°C | +1.05°C | +1.33°C | +1.60°C | +2.00°C |
| March–May 2027 | +0.23°C | +0.58°C | +0.83°C | +1.08°C | +1.43°C |
| April–June 2027 | -0.22°C | +0.14°C | +0.40°C | +0.66°C | +1.02°C |
| May–July 2027 | -0.68°C | -0.26°C | +0.03°C | +0.32°C | +0.74°C |
Probability of three-month RONI ≥ +2.50°C. These percentages are explicitly reported in the bulletin, not interpolated from the chart.
September–November 2026
54%
October–December 2026
83%
November 2026–January 2027
70%
Repeated daily checks are not new bulletins. This history only includes publications captured by this journal by the selected date.
Previous issue: 10 September 2026 · El Niño Advisory
El Niño is strengthening, with a greater than 90% chance of a very strong event during the Northern Hemisphere fall and winter 2026-27.
Official advisory status unchanged. Read the current synopsis above for NOAA’s latest assessment.
El Niño continues to strengthen, with a strong-to-very strong El Niño likely through January-March 2027 (remaining greater than an 83% chance).
First captured 2026-10-08 23:14 UTC
El Niño is strengthening, with a greater than 90% chance of a very strong event during the Northern Hemisphere fall and winter 2026-27.
First captured 2026-09-29 22:36 UTC
Tap the map to inspect the nearest sampled ocean point.
These dates describe different things: ocean observations are daily and arrive with a delay; the ENSO advisory and outlook are issued monthly, while RONI is a three-month mean updated monthly. We check for new source data hourly during the current UTC day. Previous revisions are retained and closed captures stay fixed.
RONI · last 120 captured seasons · °C
Dashed lines mark ±0.5°C. Sustained ocean anomalies and atmospheric evidence matter; crossing a line does not by itself establish an official event. Recent RONI estimates may be revised. Baseline: 1991–2020.
ASO 2025: -0.78°C
SON 2025: -0.93°C
OND 2025: -0.98°C
NDJ 2025: -1.04°C
DJF 2026: -0.91°C
JFM 2026: -0.76°C
FMA 2026: -0.44°C
MAM 2026: -0.04°C
AMJ 2026: +0.49°C
MJJ 2026: +0.97°C
JJA 2026: +1.36°C
JAS 2026: +1.69°C
Official phase probabilities · issued October 2026. These overlapping three-month seasons are forecasts, not observations. Percentages are rounded by the source; 100% is not a guarantee of local impacts.
REGIONAL CONTEXT / NOT A LOCAL WARNING
A stronger El Niño does not mean every part of the Northern Hemisphere gets the same weather. Season, location and other climate drivers matter. These short source-linked explanations are editorial context, reviewed 9 October 2026; they are not automatically refreshed forecasts.
The Met Office’s September 2026 assessment raises the likelihood of wetter, stormier conditions in autumn and early winter. This is a seasonal tendency, not a prediction of particular storms or a guarantee for the whole winter.
Met Office assessment ↗Use NOAA’s regional temperature and precipitation outlooks to see the actual seasonal probabilities. The probability of a strong ENSO index is not the probability of flooding, snowfall or drought at a particular address.
NOAA seasonal outlooks ↗The same Met Office assessment highlights increased drought risk in southern Africa and northeast Australia. ENSO’s effects extend across hemispheres; they vary between events and interact with other influences.
Global context from the Met Office ↗For immediate safety decisions, consult the warning authority for your location. This tracker is a scientific archive, not an emergency alert service.
Source checked successfully · checked 2026-10-10 00:14 UTC · last retrieved 2026-10-10 00:14 UTC
Source checked successfully · checked 2026-10-10 00:14 UTC · last retrieved 2026-10-10 00:14 UTC
Source checked successfully · checked 2026-10-10 00:14 UTC · last retrieved 2026-10-10 00:14 UTC
Source checked successfully · checked 2026-10-10 00:14 UTC · last retrieved 2026-10-10 00:14 UTC
Source checked successfully · checked 2026-10-10 00:14 UTC · last retrieved 2026-10-10 00:14 UTC
Source checked successfully · checked 2026-10-10 00:14 UTC · last retrieved 2026-10-10 00:14 UTC