El Niño Impacts 

and Outlook

Northeast Region

October 2018

Typical El Niño Winter Pattern

Highlights for the Northeast

An El Niño develops when sea surface 

temperatures are warmer than average 

in the equatorial Pacific for an extended 

time. This is important to North America 

because El Niño can impact our weather 

patterns, especially in the winter. 

Although each El Niño is different, 

there are some general patterns that 

are predictable. For instance, the polar 

jet stream is typically farther north 

than usual, while the Pacific jet stream 

remains across the southern U.S. 

The dry winter conditions that 

characterize Ohio and the Midwest 

commonly extend eastward into western 

New York and Pennsylvania. As storms 

often move up the coast during El Niño 

winters, the Eastern Seaboard generally 

experiences above-normal precipitation.

The image above shows the typical pattern in the winter during El Niño events. The 

polar jet stream tends to stay farther north than usual, while the Pacific jet stream 

remains across the southern U.S. Since much of the region lies between the two 

storm tracks, temperature and precipitation patterns vary considerably from south 

to north. The diagram above from NOAA represents general patterns and is not 

created from actual data. For more information, please visit: https://www.climate.

gov/news-features/department/enso-blog.

El Niño Outlook

Winter Temperature and Precipitation Outlooks

Valid for December 2018 - February 2019

As of mid-October, NOAA's winter outlooks (above) show that above-normal 

temperatures are favored for New England, New York, the northern half of 

Pennsylvania, and northern New Jersey. Equal chances of below-, near-, or 

above-normal temperatures are forecast for the rest of the region. Meanwhile, 

the precipitation outlook indicates that Delaware, much of Maryland and 

New Jersey, southeastern Pennsylvania, and portions of West Virginia could 

have above-normal precipitation, while equal chances are predicted for the 

rest of the Northeast. The seasonal outlooks combine many factors including 

dynamical models, the effects of long-term trends, and soil moisture, in 

addition to past El Niño patterns. Therefore, they may not match typical El Niño 

conditions exactly. 

El Niño Strength

Winter 2018-19

While ENSO-neutral conditions were 

present in the equatorial Pacific Ocean 

during September, areas of aboveaverage sea surface temperatures 

were becoming more widespread. 

According to the Climate Prediction 

Center, there is a 70-75% chance

that El Niño will form in the next few 

months and continue through winter 

2018-19. The forecast favors a weak El 

Niño event.

Northeast Region El Niño Impacts and Outlook | October 2018 

https://www.drought.gov/drought/resources/reports

Contact: Ellen Mecray (Ellen.L.Mecray@noaa.gov)

Northeast Regional Climate Center

(nrcc@cornell.edu)

Temperature Precipitation
Potential Winter Impacts

Comparisons and Limitations

Winter Conditions During Past El Niños 

The maps above illustrate the winter conditions during the record breaking El 

Niño of 2015-16. The entire region was warmer than normal, and precipitation 

was generally near to above normal. This aligns with the weather patterns 

typically seen during El Niño winters and those expected this winter. Snowfall 

signals varied across the region. While New England, New York, and northern 

Pennsylvania saw below-normal snowfall, southeastern Pennsylvania, West 

Virginia, and the Mid-Atlantic saw above-normal snowfall. Each El Niño is 

different and other factors can affect winter conditions, such pre-exisiting 

global snow cover patterns or climate variability associated with the Arctic 

Oscillation and North Atlantic Oscillation. For instance, during the winter 

of 1965-1966, expected El Niño precipitation was subdued due to a strong 

negative North Atlantic Oscillation. These patterns are less able to be forecast 

far in advance compared to El Niño, meaning it is uncertain how much they 

will affect the upcoming winter. 

Northeast Partners

Northeast Region El Niño Impacts and Outlook | October 2018 

https://www.drought.gov/drought/resources/reports

National Oceanic and Atmospheric Administration

offices including:

NESDIS/National Centers for Environmental 

Information

NWS, Eastern Region

NWS, Climate Prediction Center

NWS, National Operational Hydrologic Remote 

Sensing Center

NMFS, Fisheries Science Centers and Regional 

Office, Atlantic

NOS, Office for Coastal Management

OAR, Climate Program Office and Geophysical 

Fluid Dynamics Lab

OAR, National Sea Grant Office

NOAA's North Atlantic and Great Lakes Regional 

Collaboration Teams

And the following other offices:

Northeast Regional Climate Center

National Integrated Drought Information System

Consortium of Climate Risk in the Urban Northeast

Cooperative Institute for the North Atlantic 

Research

Northeast Region State Climatologists

Mid-Atlantic RISA

Coastal Storms Snowfall

Contact: Ellen Mecray (Ellen.L.Mecray@noaa.gov)

Northeast Regional Climate Center

(nrcc@cornell.edu)

Several research studies 

have noted an increased 

frequency of East Coast 

storms during El Niño 

winters. These storms, 

known as nor’easters, 

have a number of coastal 

impacts, ranging from 

beach erosion and high 

winds to heavy snowfall and precipitation. Storms that 

follow a classic nor’easter track from south of Cape 

Hatteras along the East Coast are the main contributor 

to this increase. Hirsch et al. (2001) found an additional 

two storms with this track occur during El Niño winters 

compared to other winters. Strong El Niño events are 

particularly associated with this increase. Significant 

snow storms such as the Blizzard of ‘58 and a second 

March 1958 nor’easter occurred in conjunction with El 

Niño conditions, as did the February 2003 Presidents' Day 

Storm. Storms such as the "Perfect Storm" in October 

1991 brought 15 to 30 foot waves to coastal New England 

during a strong El Niño. More recently, the blizzard of 

January 2016 severely impacted the Northeast during one 

of the strongest El Niños on record. 

Snowfall along the 

Northeast coast is 

typically above average 

during El Niño winters. 

The exception to this is 

the lake-effect region 

in New York. Buffalo's 

two least snowy 

winters since 1950 

occurred during strong 

El Niños. Typically, 

in regions closer to 

the coast, December 

through February snowfall is as much as 6 inches greater 

during such winters. In Washington, DC, eight of the ten 

greatest 1-day snowfalls since 1950 have occurred during 

El Niños. However, individual storm tracks can influence 

where precipitation falls as rain versus snow. Heavy East 

Coast snowfalls have negative impacts on transportation 

and the economy. Based on the Northeast Snowfall Impact 

Scale, an index that infers societal impacts based on the 

geographical extent and amount of snowfall along with 

population data, eight of the ten storms classified as 

crippling have occurred in conjunction with El Niño.

Image courtesy of nj.gov

January 2016 blizzard snow totals