Does El Niño mean more snow?

It depends where you are. In Snoflo's station record, strong El Niño winters brought more snow to Southwest (30% vs typical) and less to Pacific Northwest; the pattern held in most but not all of the 7 such winters since 1991.

Where does this data come from?

Measured records: 3246 NOAA GHCN weather stations with monthly snowfall since 1950 in every state, 700 SNOTEL snowpack sites in the West, USGS daily river discharge, and NOAA's Oceanic Niño Index, which classifies each winter as El Niño, La Niña or neutral. Anomalies are measured outcomes, not model projections.

Is this winter following the El Niño pattern?

As of 2026-11-14, 50% of 30 stations sit on the side the strong El Niño composite predicts. The page updates every day.

El Niño Atlas · every US state · measured station records since 1950 · updated daily · Nov 14, 2026

What El Niño actually does to your snow

Name: Snoflo El Niño Atlas -- measured ENSO composites for US snow and rivers
Creator: Snoflo
License: https://creativecommons.org/licenses/by/4.0/

Not a model, not a forecast: the measured record. For 3246 NOAA weather stations in every state, 700 SNOTEL snowpack sites in the West and the big river gauges, this is how strong El Niño winters compared with typical winters over 77 classified winters since 1950 — and how this winter is tracking against that pattern.

Composite anomalies from measured records (GHCN-Daily monthly snowfall since 1950 for 3246 stations, SNOTEL SWE since the early 1990s, USGS daily discharge), stratified by DJF Oceanic Niño Index: El Niño ≥ +0.5, strong ≥ +1.5, La Niña ≤ −0.5. Anomaly = class mean − all-winter mean (% of mean; days for timing); hit rate = share of class winters on the composite's side; r = Pearson correlation of the station's series with DJF ONI across all winters. Surfaces are inverse-distance interpolations of station composites, masked to coverage; dots are the measurements.

● This winter · from ENSO Watchvery strong El Nino (Niño 3.4 3.3 °C) · "strong El Niño" composite applies7 winters since 1991 fall in this class: 1958, 1973, 1983, 1992, 1998, 2016, 2024. The page tracks the current season against their measured fingerprint. ENSO Watch →

The map

Deviation from a typical winter, measured at the stations and interpolated between them. Season snowfall covers the whole country; snowpack layers come from SNOTEL in the West. Hover for the nearest station's record; tap for its state's snow report.

Fly the atlas in 3D

The same measured composites draped over real terrain — orbit the ranges, compare basins, tap any station. Free with a Snoflo account.

Winners (strong El Niño)

+30%

Southwest season snow vs typical

Losers (strong El Niño)

-46%

Pacific Northwest season snow vs typical

Most reliable signal

Ohio Valley

pattern held in 86% of station-winters

This winter so far

50%

of 30 stations on the strong El Niño side · day 44

Record depth

3946

stations in every state · 77 winters since 1950

What it means where you are

Pick any state — the verdict is computed from its long-record snowfall stations (plus SNOTEL snowpack in the West)

How often does it deliver?

Share of station-winters that landed on the expected side, by region · r = correlation with ONI

Region	Expected	Hit rate	Size	r

Regional hit rate pools every station-winter in the class; the sign is the regional median composite. Small n for the strong class is the honest caveat — these are odds, not promises.

Every winter, one station

Season snowfall each winter since 1950 — El Niño winters in red, La Niña in blue, dashed = all-winter median

El Niñostrong El NiñoLa Niñaneutral

This winter vs the pattern

Share of western SNOTEL sites whose snowpack is already on the side the composite predicts, day by day

Agreement = sign(today's % of normal − 100) == sign(composite anomaly for Apr 1 SWE), over stations whose normal for the date is ≥ 1 in. Recorded daily from the first run of this page.

Rivers: spring runoff in strong El Niño years

April–July mean discharge at the outlet gauge vs the all-year mean · gauge records since 2011, so these are short samples

River	Apr–Jul runoff	Hit rate

Peak timing

Days earlier or later the snowpack peaks in strong El Niño winters, western regions (SNOTEL)

State of the Snow Where the Rivers Go ENSO Watch Ski reports

Methods & data

Winter classes: DJF-centred ONI from the CPC table ingested for ENSO Watch; El Niño ≥ +0.5, strong ≥ +1.5, La Niña ≤ −0.5. A winter is labelled by its January year (= water year).
Season snowfall: NOAA GHCN-Daily monthly snowfall totals (Global Summary of the Month), Nov–Apr, for US stations whose snowfall record spans at least 1980–present; a winter needs Dec–Mar present. Apr 1 snowpack: SNOTEL SWE on Apr 1 (±3 days). Peak timing: season-day of maximum SWE, winters with peak ≥ 2 in. Runoff: Apr–Jul mean daily discharge at the outlet gauges used on Where the Rivers Go (streamflow.metrics.streamflow).
Eligibility: ≥ 18 classified winters per station, ≥ 3 winters in the class; NRCS/NOHRSC twin records merged (longer record kept). Skill: r is the Pearson correlation between DJF ONI and the station series over all winters; r² is the share of year-to-year variance ENSO explains, which is modest almost everywhere, so composites are odds, not forecasts.
Surface: inverse-distance weighting (p = 2, reach 3.2°, masked beyond 1.7° (snowfall) or 2.1° (SNOTEL) from any station) on a 468×200 lon/lat grid over the lower 48; hatched where fewer than 3 in 5 class winters agreed. The atlas canvas and the 3D overlay read the same PNG.
API: /api/enso/atlas (JSON, 1-h cache).

Sources: NOAA NCEI GHCN-Daily, NRCS SNOTEL, USGS NWIS, NOAA CPC ONI. Lower 48 on the map; Alaska stations in the tables. Measured outcomes, 77 winters; strong-class sample sizes are small and shown with every number.