NOAA Winter Forecast 2026–2027: El Niño, Snow and the October Date

NOAA’s flagship U.S. Winter Outlook for 2026–27 is not out. It has landed on the third Thursday of October for four years running, and the third Thursday of October 2026 is the 15th — which is also the date on the Climate Prediction Center’s own published release calendar.

What NOAA has published is a genuine forecast for this winter, and it is unusually loaded. The agency has an El Niño Advisory in force and its forecasters put a greater than 90% chance on the event reaching the “very strong” tier between October and December. If that happens, the 2026/27 winter will be shaped by one of the largest El Niño events in the record going back to 1950.

That is a real signal, and it is worth being precise about what it does and does not tell you. It tilts the odds across whole regions over three months. It does not tell you whether it will snow at your house in January — and NOAA does not forecast snowfall totals at all.

What is the 2026/2027 US winter forecast?

Wetter than normal across the southern tier, drier from the Pacific Northwest through the northern Plains and Great Lakes, and milder than normal over most of the country apart from the south — a textbook El Niño winter, and a sharp reversal of last year.

That table summarises the Climate Prediction Center’s own long-lead discussion for the seasons running into winter 2026-27. The forecaster’s wording is that El Niño teleconnections “ramp up through the fall 2026 and winter 2026-2027”, with below-normal precipitation over the Northwest and north-central states “juxtaposed with above-normal precipitation over the southern tier, with highest probabilities over parts of the Southeast in winter 2026-2027 when teleconnections are strongest”.

One nuance worth keeping: a strong El Niño would normally also push the Gulf States drier in places, but CPC has left parts of that region at equal chances, because the dynamical models disagree and the recent decadal trend runs the other way.

Is it El Niño or La Niña this winter?

El Niño, and a fast-strengthening one. The Pacific flipped from a weak La Niña to a strong El Niño in about six months.

Chart: NOAA’s Oceanic Niño Index, the three-month running mean of Niño-3.4 sea surface temperature anomalies. Only completed seasons are plotted.

This matters because a lot of coverage still circulating online describes the coming winter as a La Niña winter. It is not. Here is the index, season by season through 2026:

May–July is still the last completed season, checked again on 21 August. The index is a three-month running mean, so June–August cannot exist until August does.

NOAA’s 9 July diagnostic discussion put the latest weekly Niño-3.4 reading at +1.2 °C, with the far-eastern Niño-1+2 region at +2.7 °C, and described a downwelling Kelvin wave deepening the thermocline. The SST consolidation forecast reaches just under +2.5 °C by late autumn.

The probabilities NOAA attached in that July discussion: a 97% chance El Niño persists through early spring 2027, an 81% chance it is very strong during October to December, and 75% for November to January.

Those have since firmed. The 13 August discussion puts a very strong event at greater than 90% for Northern Hemisphere autumn and winter, and adds a figure the July one did not carry: a 69% chance that October to December produces a historic event exceeding every El Niño back to 1950, meaning a three-month RONI of +2.5 °C or more. The Niño-3.4 index averaged +1.4 °C across July, and subsurface anomalies reached +10.0 °C at depth.

What did past strong El Niño winters actually do?

All eight of the strongest El Niño winters since 1950 were wetter than the US average. Six of the eight were warmer — and two were among the coldest fifteen winters in the record.

Chart: NOAA nClimDiv contiguous-US December-February average temperature. The marked winters are those whose Oceanic Niño Index peaked at +1.6 °C or higher.

We pulled NOAA’s national temperature and precipitation series for every winter since 1950 and looked at what the strong El Niño years actually delivered, rather than at what the composite maps say they should. The two right-hand columns are that winter’s rank out of 77, warmest and wettest first:

There is an interactive version of this table. Our US winter outlook explorer lets you move the ONI threshold and watch the hit rate change — at +1.6 every one of the eight was wetter than average, but drop the bar to +1.0 and it falls to 13 of 16. It also carries NOAA’s regional outlook for this winter, kept separate because that is a forecast and this table is not.

Two things fall out of that table.

The precipitation signal is the reliable one. Every single strong El Niño winter came in above the 1950-2026 average of 6.80 inches — although 1965-66 only just, by six hundredths of an inch. Two of them, 1997-98 and 1982-83, are the second and third wettest winters in the entire record.

The temperature signal is much weaker than its reputation. Five of the six warm ones are from 1982-83 onwards, the exception being 1957-58; the two cold ones are both from before 1975. That pattern is entangled with the warming trend running through the whole series, so “El Niño means a mild winter” is doing less work than it appears to. 1972-73 had a stronger El Niño than 1982-83 and was 4.3 °F colder.

For context on what you are comparing against, last winter — a weak La Niña — was the second warmest DJF on record at 37.07 °F and the fourth driest at 5.02 inches. The summer that followed it produced the July heat wave that ran across most of the eastern United States and an extreme heat watch across the Mid-South , so the ground the coming winter starts from is warm and, in much of the west, dry.

Will it snow more or less this winter?

More in the southern mountains and the southern tier, less across a much larger northern area — and NOAA’s own phrase for El Niño is “the great snowfall suppressor over most of North America”.

The short version: above-average snow shows up in California, Nevada, Utah, Colorado, New Mexico and Arizona, on the high plains and in the Mid-Atlantic and southern Appalachians; below-average snow shows up from the Pacific Northwest through the northern Rockies and Great Lakes to interior New England and Alaska. Wetter is not the same as snowier, because the southern tier is wetter partly by being milder.

We have given snow its own page, because the region-by-region picture and the reasons a stronger event does not mean more snow need more room than a section: 2026-27 US El Niño snow predictions .

When does NOAA’s winter forecast actually come out?

The one everybody means is not out yet, and the date to put in the diary is Thursday 15 October 2026.

There are two different NOAA products with a claim on the phrase “winter forecast”, and almost every argument about this topic is really two people talking about different documents.

The flagship U.S. Winter Outlook is the one with the press release and the three coloured maps of the country — temperature, precipitation and drought, for December through February. It is issued once a year, in October, and it is what a news story means when it says NOAA’s winter forecast is out.

The long-lead seasonal outlooks are the monthly workhorse. The Climate Prediction Center reissues a rolling set of them every month, each covering the next twelve overlapping three-month seasons — which means a December-February 2026/27 forecast has already been in the set for months, and simply gets reissued at a shorter lead each time. The current one was issued on 20 August. It is a real NOAA forecast for this winter. The regional tilt set out above is read from the set before it, issued 16 July, which we went through line by line; we have not yet worked through the 20 August release, and this page will keep saying so until we have.

Why 15 October, and how firm is that?

Firm on the schedule, and a four-year pattern on the press release. Two separate things point at the same day.

The Climate Prediction Center publishes its release calendar in advance. Its own wording is that forecasts “are released on the third Thursday of the month”, generally around 8:30 AM Eastern. The four releases that carry us into winter, with the August release now past:

That is the schedule, published by NOAA, and 15 October is a fact on it rather than a guess.

What is a pattern rather than a promise is the flagship. NOAA has issued its Winter Outlook on that same October release day four years running:

NOAA has not announced the 2026–27 date. Four years is a pattern, not a commitment, and the honest form of the claim is: the seasonal outlook release is scheduled for 15 October, and the flagship has accompanied that release every year we checked.

So what is published right now?

The 20 August set is the current one: the Climate Prediction Center’s long-lead prognostic discussion for it is timestamped 8:30 AM EDT on Thursday 20 August 2026. The regional tilt quoted higher up this page is still the 16 July set’s, because that is the one we have read in full.

The 10 September date is not our inference either. The 13 August discussion ends by naming it: “The next ENSO Diagnostics Discussion is scheduled for 10 September 2026.”

The practical consequence for a reader in August. Anything you see today headlined “NOAA’s winter forecast” is describing the monthly seasonal outlook, not the flagship — which is fine, because the monthly outlook is a genuine NOAA product covering this winter. What it is not is necessarily the newest. The version most stories are written from went out on 16 July; a fresher set landed on 20 August, and the next lands on 17 September.

Three things could still move the picture between now and October: whether the event peaks near +2.5 °C or falls short, how the Madden-Julian Oscillation behaves through the winter, and whether the polar vortex holds. None of the three is settled in August, and the last two are essentially unpredictable at this range.

The bottom line

The 2026/27 US winter will be an El Niño winter, very likely a strong one, and NOAA gives it a real chance of ranking among the biggest events since 1950. The official tilt is wetter across the south with the Southeast most strongly favoured, drier across the Northwest and the northern tier, and milder over most of the country outside the southern states.

The historical record supports the wet part more firmly than the mild part. Every strong El Niño winter since 1950 was wetter than average; two of them were among the coldest in the record. If you want one sentence to carry through to December: El Niño reliably moves the storm track, and much less reliably moves the thermometer.

Sources

Checked 21 August 2026. No affiliate links, and no payment was received for any link on this page.

Seasonal outlooks are probabilistic statements about three-month averages over large regions. They are not forecasts of individual storms, snowfall totals or conditions on any given date. For decisions that depend on actual weather, use your local National Weather Service forecast office.