Winter 2026-27
Winter 2026-27: El Niño and the patterns to watch
NOAA’s Climate Prediction Center has an El Niño Advisory in effect for winter 2026-27. In its September 10, 2026 update it said El Niño is strengthening, with a greater than 90% chance of a very strong event this fall and winter.
The Weather Decision Solutions forecast desk sees a strong El Niño as potentially one of the most beneficial patterns the US has had in years: an active southern storm track, an exceptional Sierra Nevada snowpack, drought relief and fewer long Arctic outbreaks across the northern US and Northeast.
The same storm track raises flood and landslide risk in places, and no two El Niño events are exactly alike. This page covers the patterns that decide each storm, when the official outlook updates and how to follow the season. The forecast desk’s full region-by-region outlook is on weatherdecisionsolutions.com.
Where El Niño stands
- Official status
- El Niño Advisory
- Latest update
- September 10, 2026. El Niño is strengthening, with a greater than 90% chance of a very strong event this fall and winter.
- Next update
- October 8, 2026
- Where to check
- NOAA Climate Prediction Center ENSO Diagnostic Discussion
El Niño is a warming of the tropical Pacific Ocean that shifts the jet stream over North America. Its effects on the US show up mainly through the cool season. No two events are exactly alike, and the outcome depends on how El Niño interacts with the Arctic Oscillation, the North Atlantic Oscillation and the Pacific Decadal Oscillation.
From the WDS forecast desk
The regional outlook in one line each
The Weather Decision Solutions forecast desk published its winter 2026-27 outlook in nine regions. Here is the short version. What each region could gain, and what it still puts at risk, is in the full regional outlook. For the official government view, see the Climate Prediction Center seasonal outlooks.
- Southern California. The wettest pattern on the map.
- Central and Northern California. Snowpack as a natural reservoir.
- Desert Southwest and Great Basin. Drought relief and lower fire risk.
- Pacific Northwest and Northern Rockies. Mountain snow and hydropower.
- Southern Plains. Rain for winter wheat.
- Gulf Coast and Southeast. A quieter Atlantic season.
- Ohio and Lower Mississippi Valleys. Soil moisture and working rivers.
- Northern Plains and Upper Midwest. Fewer Arctic outbreaks.
- East and Northeast. Milder lean, storms still possible.
Patterns to watch besides El Niño
El Niño sets the tone for the season. Whether cold air and a storm arrive in the same place on the same weekend depends on shorter patterns that swing over days to weeks. Forecasters call them teleconnections, because they link weather in places far apart.
NOAA lists these patterns on its Climate Prediction Center pages, and most of them are read on upper-air maps. The 500 mb map guide shows how.
NAO (North Atlantic Oscillation)
A pressure seesaw between Iceland and the Azores that helps steer storms across the North Atlantic.
When the NAO is negative, the jet stream tends to buckle and cold air can reach the eastern US and Europe more easily. A positive NAO usually means a faster flow and a milder East.
AO (Arctic Oscillation)
A ring of pressure around the Arctic that works like a gate for cold air.
In its negative phase the gate opens and cold air tends to spill south into the US and Europe. In its positive phase the cold stays closer to the pole.
PNA (Pacific/North American pattern)
A chain of high and low pressure running from the Pacific into eastern North America.
In its positive phase, a ridge over the West and a trough over the East tend to bring cold air into the East. The negative phase tends to flip that setup.
MJO (Madden-Julian Oscillation)
A pulse of tropical thunderstorms that travels eastward around the globe in roughly 30 to 60 days.
The phase it is in can nudge the US pattern a couple of weeks later, so forecasters check it for the two to four week range.
Polar vortex
A band of strong winds high in the stratosphere circling the Arctic, enclosing a pool of very cold air. It is not the same thing as the polar jet stream, which is lower and closer to the weather.
Research links a weakened or disrupted vortex, as in a sudden stratospheric warming, to cold air outbreaks in the US or Eurasia a few weeks later. A weak vortex is a reason to look closer, not a promise of cold.
The Pacific Decadal Oscillation, a slower pattern in North Pacific water temperatures, can also change how a given El Niño plays out, which is one reason two strong events can look different.
When the outlook updates
The Climate Prediction Center issues its ENSO Diagnostic Discussion on the second Thursday of each month at 9:00 a.m. Eastern. It states whether El Niño or La Niña is present and gives the odds for the months ahead. The center’s monthly and seasonal temperature and precipitation outlooks follow on a Thursday near the middle of the month.
| Next ENSO updates | Usual schedule |
|---|---|
| October 8, 2026 | Second Thursday of the month |
| November 12, 2026 | Second Thursday of the month |
| December 10, 2026 | Second Thursday of the month |
| January 14, 2027 | Second Thursday of the month |
Dates assume NOAA keeps its usual schedule. The probabilities on this page are as of the September 10, 2026 update, so check the Climate Prediction Center page for the newest numbers.
How to follow the season in 4070
4070 Pro puts the long-range tools next to the models, so you can follow the season and then watch each storm arrive. Pro is seven days free, then $14.95 a month, and every tool below is included.
| Tool | What it shows |
|---|---|
| Indices | Follow El Niño, La Niña, AO, NAO, MJO and other drivers through observed history, available projections and typical weather effects. |
| 4-Week Outlook | See the climate drivers shaping the next few weeks and what they could mean for your region. |
| 9-Month Outlook | Scan nine months of regional temperature and precipitation guidance, then open any cell for model agreement, confidence and explanation. |
| CFSv2 seasonal snowfall | View supported monthly and three-month snowfall water-equivalent totals and departures. This is liquid content, not forecast snow depth. |
| Storm Tracks | Follow developing lows through the GEFS and Euro ensembles and recent runs of GFS, GFS AI, Euro, Euro AI and HRRR. Paths show model support, not a probability or impacts. |
Long-range guidance comes from many model runs, and the spread between them is part of the answer. The ensembles guide explains how to read that spread, and how to read weather models covers the basics.
Need a site-specific commercial winter forecast for a business? Weather Decision Solutions offers one: see the WDS winter forecast.
Questions people ask
Is winter 2026-27 an El Niño or La Niña winter?
El Niño. NOAA’s Climate Prediction Center has an El Niño Advisory in effect, and its September 10, 2026 update said El Niño is strengthening, with a greater than 90% chance of a very strong event this fall and winter. The next update is October 8, 2026.
What weather does El Niño bring to the US in winter?
The Weather Decision Solutions forecast desk expects a strong El Niño to make an active Pacific storm track across the southern US more likely. That could mean rain for California, the Southwest and parts of the Southern Plains, a large Sierra Nevada snowpack, stronger wind shear that tends to suppress Atlantic hurricanes, and often fewer prolonged Arctic outbreaks across the Midwest, Great Lakes and Northeast. No two El Niño events are exactly alike. The full region-by-region outlook is at weatherdecisionsolutions.com/el-nino.
Will El Niño mean more snow where I live?
Not by itself. The forecast desk’s view is a lot of mountain snow across the West and a milder lean with fewer long Arctic outbreaks across the northern US and Northeast, where winter storms remain possible. Snow needs cold air and a storm in the same place at the same time, and shorter patterns such as the NAO and AO help decide that.
How much snow will we get this winter?
Nobody can give a trustworthy snow total for a whole winter. Seasonal outlooks can lean a region warmer, colder, wetter or drier, and a model such as CFSv2 can show a seasonal snowfall pattern, but individual storms only come into focus about a week or two out. Treat any season total as a tilt in the odds.
When does NOAA update the El Niño forecast?
The Climate Prediction Center issues its ENSO Diagnostic Discussion on the second Thursday of each month at 9:00 a.m. Eastern. The next dates are October 8, November 12 and December 10, 2026, and January 14, 2027, assuming the usual schedule. Its monthly and seasonal temperature and precipitation outlooks come out on a Thursday near the middle of the month.
What are teleconnections, and how are they different from El Niño?
Teleconnections are large pressure and wind patterns, such as the NAO, AO and PNA, that link weather in distant places. El Niño is a slow warming of the tropical Pacific that sets the tone for a whole season. The teleconnections swing over days to weeks and often decide whether a cold air outbreak or a storm track shows up in your area.
Does El Niño make hurricane season quieter?
It tends to. NOAA says El Niño increases vertical wind shear over the tropical Atlantic, which can tear developing storms apart, so Atlantic hurricane activity is often suppressed. A quieter season can still produce a damaging landfall.
Sources
- NOAA Climate Prediction Center: ENSO Diagnostic Discussion Status, probabilities and next update date, read October 6, 2026.
- NOAA Climate Prediction Center: seasonal outlooks Official temperature and precipitation outlooks.
- NOAA Climate Prediction Center: teleconnection indices NAO, AO and PNA.
- NOAA Climate Prediction Center: Madden-Julian Oscillation
- NOAA Climate.gov: Understanding the Arctic polar vortex
- NOAA Climate.gov: El Niño, La Niña and the Atlantic hurricane season