El Niño May Be 'Historically Strong' In 2024: What It Means For PA

PENNSYLVANIA - The El Niño climate pattern associated with coastal storms, temperature swings and snowier late winters in the region may top records this year, climate experts say.

There’s a 54% chance that El Niño, known for bringing high-moisture winter storms like the fierce systems Pennsylvania saw this week, will end up “historically strong” and ranking in the top 5 on record, Michelle L’Heureux, a meteorologist with the The Climate Prediction Center, wrote last month. Read more: Water Rescue, Power Outages, School Delays: See PA Storm Aftermath

That tracks with AccuWeather's 2023-24 winter outlook, which predicts there could be multiple nor'easters to the state in January and February dumping inches of snow compared to the below-average amounts that the majority of Pennsylvania saw over the relatively weak 2022-23 winter.

"The window for snow-producing nor'easters will open in late January through February which could dish out hefty snowfall amounts to Boston, New York City, Philadelphia and beyond," AccuWeather predicted, noting "a strengthening El Niño will make this winter different than last year."

The “historically strong” El Niño status will arise if the three-month-average temperature of the central tropical Pacific Ocean, specifically in the Niño-3.4 region, is 2°C hotter than the average range.

Current models from the The Climate Prediction Center show that El Niño will end April­ to June, with a La Niña event in the cards for July to September. That weather pattern typically means lower precipitation totals and more rain than snow for Pennsylvania.

In most El Niño winters, Pennsylvania has below-average snowfall from January to March everywhere but the southeast portion of the state, which typically sees a bit more snow than average. In moderate to strong El Niño winters, we normally see much less snowfall in the northern and central parts of the state. Pittsburgh typically sees less snow in these winters, while Philadelphia will typically gain a few inches.

This year’s El Niño, which began developing in June, is the first in four years. Not all El Niños are the same, and that adds uncertainty to winter forecasts, according to The Weather Channel. In general, the forecast calls for warmer-than-average temperatures in the northern U.S. from the Great Lakes to western Canada to Alaska; drier-than-normal conditions in the Midwest and Ohio Valley; wetter conditions in the Southwest; and cooler-than-normal temperatures in the South and Southeast.

The winter of 2015-16 was the warmest U.S. winter on record, and the El Niño that year was one of the strongest on record. Experts say that the current El Niño could mean sweltering temperatures in 2024.

“El Niño impacts on global temperature typically play out in the year after its development, in this case in 2024,” WMO secretary-general Petteri Taalas told EuroNews, adding that, due to record-high land and sea surface temperatures in June 2023, this year could be even warmer.

But just because El Niño winters often mean lower snowfall totals overall, fierce storms aren’t out of the question, as Pennsylvanians saw this week.

Another winter storm is set to hit the state Friday, this time bringing up to two inches of rain, damaging winds and a chance of coastal flooding due to the snow melt and saturated ground from this week’s earlier storms.

The heaviest rain is expected in North Jersey and northeast Pennsylvania Friday night through Saturday morning, with precipitation to begin around the late afternoon, the National Weather Service said. The risk of river flooding will continue through the weekend. Read more: New Winter Storm Poses Same Flood, Wind, Outage Threats To PA

Here’s the latest forecast, according to the National Weather Service:

Thursday: Sunny, with a high near 46. Southwest wind 5 to 10 mph.

Thursday Night: Mostly clear, with a low around 32. Southwest wind 5 to 10 mph becoming west after midnight.

Friday: A chance of rain after 5 p.m. Increasing clouds, with a high near 46. Northwest wind 5 to 10 mph becoming southeast in the afternoon. Chance of precipitation is 30%. New precipitation amounts of less than a tenth of an inch possible.

Friday Night: Rain. Low around 44. Breezy, with a southeast wind 15 to 20 mph increasing to 20 to 25 mph after midnight. Winds could gust as high as 45 mph. Chance of precipitation is 100%. New precipitation amounts between a half and three quarters of an inch possible.

Saturday: A slight chance of rain before 1 p.m. Mostly sunny, with a high near 55. Breezy, with a west wind 15 to 20 mph, with gusts as high as 35 mph. Chance of precipitation is 20%.

Saturday Night: Mostly clear, with a low around 30.

Sunday: Mostly sunny, with a high near 41.

Sunday Night: Mostly cloudy, with a low around 23.

Related: El Niño Winter: What Do Persimmons And Woolly Worms Say?