How to use this tool
- Pick your city or ski area: search, choose from the list, tap a popular location, or use your location (it stays on your device).
- Read NOAA's outlook for Dec 2026–Feb 2027: the chance that temperature and precipitation end up above, near or below normal.
- Check how strong El Niño is right now, from NOAA's latest ENSO discussion.
- See what happened before: total snowfall at the nearest long-record NOAA station in each of the 9 strong El Niño winters since 1950, as a percentage of normal.
The address bar updates as you choose (for example ?loc=chicago-il), so you can share the result.
How El Niño affects US winters
El Niño is a warming of the tropical Pacific that shifts the jet stream. In a typical El Niño winter the storm track runs farther south, so the southern US tends to be wetter and cooler while the northern tier tends to be milder and drier. That doesn't mean more snow everywhere in the south or less snow everywhere in the north: snow needs both moisture and cold air, and a wetter winter can fall as rain.
For this winter, NOAA's Climate Prediction Center (Sep 17, 2026 outlook) shows a wet signal across the southern and central US and up the Atlantic coast into New England, a weak dry tilt in the interior Northwest and Great Lakes, and above-normal temperatures favored across the interior Northwest and northern tier. NOAA also notes a negative Pacific Decadal Oscillation, which may dampen typical El Niño impacts. Read the full prognostic discussion (opens in a new tab).
How to read NOAA's probabilities
NOAA's seasonal outlook doesn't say how many inches of snow will fall. For each place it gives the chance that the season ends up in the upper, middle or lower third of the 1991–2020 record. With no information, each third has a 33% chance. A map area labeled "40–49% Above normal" means NOAA thinks the upper third is the most likely outcome — but there is still roughly a 50–60% chance it isn't. "Equal chances" means NOAA sees no strong tilt either way, not that the winter will be normal.
How strong is this El Niño?
NOAA's status is El Niño Advisory (issued Sep 10, 2026): “El Niño is strengthening, with a greater than 90% chance of a very strong event during the Northern Hemisphere fall and winter 2026-27.” The latest 3-month values (JAS 2026) are RONI +1.69 °C and ONI +2.16 °C; the weekly Niño-3.4 anomaly for the week of Sep 30, 2026 was +3.2 °C. NOAA puts the chance that October–December 2026 beats every event since 1950 (RONI ≥ +2.5 °C) at 75%.
| Strength (RONI) | Chance |
|---|---|
| Very strong (≥ +2.0 °C) | 75% |
| Strong (+1.5 to +2.0 °C) | 21% |
| Moderate (+1.0 to +1.5 °C) | 4% |
| Weak (+0.5 to +1.0 °C) | 0% |
| Neutral or La Niña | 0% |
Strength isn't destiny. NOAA stresses that a stronger El Niño raises the odds of typical impacts but never guarantees them.
How we calculate the history
We treat a winter as a strong El Niño winter if its peak 3-month index between Jun–Aug and Feb–Apr reached +1.5 °C or more by either ONI or RONI. That gives 9 winters since 1950: 1957-58, 1965-66, 1972-73, 1982-83, 1991-92, 1997-98, 2009-10, 2015-16, 2023-24. The “Big Three” (1982-83, 1997-98, 2015-16) are NOAA's own term for the strongest events.
- Season total = sum of monthly snowfall from July through June. A trace counts as zero.
- Valid season: every month from October through April must have a monthly total with no more than 3 missing days. If not, the winter shows “No data”.
- Normal = NOAA's 1991–2020 snowfall normal for the station. If NOAA has none, we use the average of at least 15 complete seasons from 1991-92 to 2020-21 and say so.
- % of normal = season total ÷ normal × 100, rounded. Hidden if normal is under 1 inch or fewer than 5 winters are valid.
Example: New York (Central Park). normal 29.8 in. In 1997-98 the park got 5.5 in (18% of normal); in 2015-16 it got 32.8 in (110%). Overall it was above normal in 3 of 9 strong El Niño winters, median 72%.
Full details, the station list and our update log are on the method & sources page.
Location pages
Locations with enough snow (normal of 5+ inches) and complete records for at least 6 of the 9 winters have their own page. Places where snow is rare are still in the picker above.