How will El Niño affect the Brockton area this winter? Everything you need to know

This winter will likely bring warmer-than-average temperatures and above average precipitation to the Brockton area, according to the National Weather Service Climate Prediction Center’s 2023-2024 U.S. winter outlook.

According to the National Oceanic and Atmospheric Administration (NOAA), this year’s seasonal outlook is driven by a climate pattern called El Niño, a weather phenomenon that begins with the warming of the ocean’s surface in the central and eastern tropical Pacific Ocean.

“The warmer waters cause the Pacific jet stream to move south of its neutral position. With this shift, areas in the northern U.S. and Canada are drier and warmer than usual. But in the U.S. Gulf Coast and Southeast, these periods are wetter than usual and have increased flooding,” NOAA says on its website.

In Massachusetts, meteorologists are predicting both above average precipitation and temperatures due to the strengthening El Niño.

“These outlooks provide critical guidance on the upcoming season for many industries and sectors of our economy, from energy producers to commodities markets to agricultural interests to tourism,” said Sarah Kapnick, Ph.D., NOAA chief scientist.

Here’s what Brockton residents should know going into the winter months ahead.

When was the last El Niño weather event?

According to NWS meteorologist Bill Leatham, this is the first El Niño pattern in the last four years, and it’s expected to be a strong one. “I looked at climate data from 1950 onwards in Boston, Hartford, Providence, and Worcester. There were seven strong El Niño’s in 1957-58, 1972-73, 1982-83, 1991-92, 1997-98, 2009-10, and 2015-16. In all those years, we had above normal temperatures and precipitation. However, snowfall was below normal,” he said.

How will El Niño affect temperatures in Brockton this winter?

According to the NWS’ 2023–2024 U.S. winter outlook map, released on Oct. 19, Massachusetts will have a 40–50% chance of above average temperatures in December, January, and February.

How will El Niño affect precipitation in Brockton this winter?

Eastern Massachusetts, including the Brockton area, will see a 33–40% increased chance of above average precipitation, according to the NWS’ 2023-2024 U.S. winter outlook map. However, according to Leatham, snowfall is harder to predict. “For snowfall, we can really only predict up to two weeks ahead of time. It depends on what the temperature is when those systems move through,” he said.