A heavier-than-usual winter might be forming on both sides of the country in Kansas City, Mo. The European Centre for Medium-Range Weather Forecasts, or ECMWF, in its September seasonal forecast states that there is a clear sign that above-average rainfall will occur over most of the West Coast and in some parts of the East Coast from December 2026 through February 2027. Even though the signal over the central United States is not as strong, it does indicate that the winter will be wetter than normal.
It is an outlook for a three-month period and not a forecast for any particular week; it does not suggest that it will rain every day in California or that each storm which moves over the Plains will turn into snow. The thing it does offer, though, is an early indication of the areas in which precipitation might exceed normal levels as a result of the effect of El Niño on the winter pattern.
A pronounced wet signal in the West
On the ECMWF precipitation map the Pacific Coast is clearly visible; northern and central California, as well as Oregon and Washington, all display higher-than-normal precipitation, and some of the most substantial projected surpluses are found close to the coast. When this pattern continues, the area might experience a series of active winter storms.
The wet weather pattern goes beyond the coast, reaching into parts of Nevada, Arizona, Utah, and the southern Rockies. This means that a wet forecast for the West Coast also affects areas farther inland. Storms can bring moisture well past where they first hit land.
Since most of California’s annual rainfall occurs during the cooler months, even minor changes in winter storms can have an effect. Yet a seasonal map cannot indicate whether the rain will fall in steady, manageable quantities or whether it will come in a small number of heavy storms. It is still too early to know what each community will experience.
Florida and the Atlantic Coast stand out
Another region which is expected to receive more rain is Florida and the Southeast. The European model indicates greater-than-normal precipitation in the area around Florida, in the eastern Gulf of Mexico, and off the Southeast coast. This wetter pattern also extends into southern Georgia and the Carolinas.
More to the north, the forecast indicates that wetter weather will occur in parts of the Atlantic Seaboard, such as the Mid-Atlantic region and New England. The Texas Gulf Coast and Louisiana are also expected to experience weather that is wetter than normal.
There is a well-known tendency among El Niño events for an active storm track to occur over the southern part of the United States and into the east. However, the fact that this is familiar does not mean that it will happen automatically. The precise course of winter storms is capable of changing, and a shift involving even a relatively small distance may result in one area receiving a heavy amount of rainfall while another gets considerably less.
The central states are a closer call
For Kansas City and a large part of the country’s interior the forecast is not very impressive. The ECMWF forecast indicates a small possibility of above-average precipitation in some areas of the Plains, the Midwest, the Great Lakes, and the Ohio Valley. This wider pattern includes states such as Kansas, Nebraska, Missouri, Iowa, Illinois, Indiana, Ohio, Michigan, and Kentucky.
A slight increase in expected precipitation is worth noting, but it does not guarantee a stormy winter. When a forecast is close to average, the actual outcome can go either way. A few big storms could make the season seem wet, but there could still be long periods of calm in between.
The type of precipitation is another open question. A warmer-than-normal winter can still produce snow or ice if moisture arrives during a spell of cold air. For residents in the central states, that’s often the detail that matters most—not just how much precipitation falls over three months, but when it falls and what the temperature is at the time.
Some areas lean drier
The weather forecast does not show uniformly wet conditions; there are areas that are drier than average in parts of the northern Rockies and the Great Basin, such as sections of Idaho, Montana and Wyoming. There is also a smaller area of dryness near the Tennessee Valley, in northern Alabama and southern Tennessee, and another narrow region close to Michigan’s Upper Peninsula.
Southern Arizona and a large part of northern Mexico are shown as being drier than usual on the map, and so too are the areas of the upper Midwest, such as Minnesota and the Dakotas, which are instead close to average. This illustrates that a national winter forecast does not show all the local variations and is not a script that every storm has to follow; in previous El Niño winters the outcomes have been different across the interior of the country, some places ending up wetter than average in one winter and drier in another.
This helps to account for the contrast in the outlook. Near the coast areas the wet signals are clear, whereas in the central states there is only a slight change. It may appear that the entire country will have a wet winter, but the actual usefulness of the forecast lies in the fact that it shows how much the outlook varies from region to region. For precipitation to occur you need both moisture and cold enough air, which have to arrive at the same time. A storm that results in rain in one city could cause snow or freezing rain further north. Precipitation outlooks for the season alone cannot answer that question.
What to watch this fall
As winter approaches the ECMWF seasonal forecast will be updated; each update may result in the wet regions becoming stronger or weaker or in their position changing. At the same time, the forecasters will gain more knowledge regarding the way in which El Niño and other weather patterns are developing.
At the moment, the key fact is that the September forecast indicates the wettest conditions will be found along the West Coast and in the eastern and southeastern parts of the United States, while most of the central U.S. is only a bit wetter than normal. It should be understood that this is merely an early indication and not a storm warning. The forecasts you’ll need for a particular trip, school day, or winter event will be available closer to the actual date.
