official data (NOAA / CPC ENSO Diagnostic Discussion)
NOAA raises historic-strength El Niño odds to 75% for October–December
CPC’s September 10 ENSO discussion says El Niño is strengthening, with greater than 90% odds of a very strong event into winter — and a 75% chance that October–December 2026 becomes a historic-strength event exceeding every El Niño back to 1950.
Key facts
- Status
- El Niño Advisory · issued 10 Sep 2026 by CPC/NCEP/NWS
- Synopsis
- El Niño strengthening · >90% chance of a very strong event during NH fall/winter 2026–27
- Observed (August / recent)
- Eastern equatorial Pacific SST anomalies exceeding +3.0°C; Niño-3.4 +1.8°C · Niño-3 +2.5°C · Niño-1+2 +3.4°C · Niño-4 +0.1°C; subsurface widely >+10.0°C
- Historic-strength (OND 2026)
- 75% chance of historic event exceeding previous El Niños back to 1950 — defined as +2.5°C or more for a 3-month RONI
- Strength table (Issued Sep 2026)
- OND RONI ≥ +2.0°C probability 98% (very-strong bin); companion text carries separate 75% historic (≥ +2.5°C RONI)
- Next
- Next scheduled discussion 8 October 2026 · live weekly = CPC ENSO current-conditions — see live HUD
“Historic-strength” is CPC’s own threshold language — not Desk hype. A three-in-four official chance that OND clears +2.5°C RONI, on top of >90% very-strong odds into winter, is the seasonal amplifier sitting under the Copernicus August heat card.
Desk reading of NOAA/CPC ENSO Diagnostic Discussion 10 Sep 2026
Note
On September 10 the U.S. climate desk stopped talking about a maybe. CPC’s El Niño Advisory says the event is strengthening, eastern Pacific anomalies already past +3°C in places, Niño-3.4 at +1.8°C, and subsurface heat still extreme. The headline number for the board: 75% chance that October–December 2026 is a historic-strength El Niño — stronger, on CPC’s RONI definition, than any since 1950. Separately, the strength table puts very strong (≥ +2.0°C) OND odds near certainty (98%). That is the same ocean that just helped Copernicus stamp a joint-hottest month. Impacts are probabilistic; the strength call is official.
Attribution: NOAA/NWS Climate Prediction Center — ENSO Diagnostic Discussion, 10 September 2026. Companion: CPC ENSO Strength Probabilities page, Issued September 2026. The Watchers 11 Sep piece = intake seed only.
Why it matters
Stronger events tilt impact odds harder; they do not guarantee every regional outcome. Desk cites CPC probabilities as stamped — no homemade El Niño gauge.
Sources
- NOAA Climate Prediction Center / NCEP / NWS
- CPC ENSO Strength Probabilities
- ENSO Diagnostic Discussion (ensodisc.html twin)
Official data. Live values go to the HUD / source product.