We are pushing through the fall season and many are asking the question: What kind of winter can we expect? El Niño is present in the Pacific Ocean and is forecast to grow stronger as we move deeper into the late fall and winter.
What is El Niño?
The El Niño Southern Oscillation (ENSO) is the name of the revolving cycle of warmer and colder surface waters of the equatorial Pacific Ocean. It is classified as an El Niño event when waters are warmer than average. The name La Niña is assigned to the colder-than-normal counterpart. Both patterns alter global temperature and precipitation patterns.
When ocean waters are anomalously warm, the likelihood of rising air and thunderstorm development increases in the vicinity of the anomaly. As the exchange of warmth and moisture from the water to the air above occurs, it rises up into the atmosphere. That rising air leads to lower pressure, thunderstorm development and wetter conditions. Away from the warmer waters at the equator will be a zone favoring higher pressure, sinking air and drier conditions. These circulation patterns are called “Hadley Cells” and result in a domino effect of localized climate anomalies for temperatures and precipitation across the world.
How does El Niño influence our weather?
The strength of El Niño can play a role in our weather across the United States during the year. El Niño is forecast to be strong this winter.
The images below show how the strength of El Niño is expected to increase into the winter season.
The numbers above zero represent the El Niño strength and the numbers below zero represent the La Niña strength.
The image above is from the Climate Prediction Center/NCEP. You can see on the bottom panel how the trend from a La Niña to an El Niño has been progressing since spring.
Historical El Niño and La Niña episodes above. Climate Prediction Center/NCEP
You can see how we have been through a long period of La Niña — the negative numbers on the chart — and have been transitioning into El Niño since the spring 2023.
Normal winter in Youngstown
The winter season, climatologically speaking, refers to the months of December, January and February.
The average temperature during a normal winter in Youngstown is 29.3°F while the average snowfall during a normal winter is 49.5 inches.
Keep in mind, snow does often fall before the month of December. The winter season only accounts for December through February.
El Niño’s influence on U.S. temperatures during STRONG episodes
El Niño can influence weather patterns throughout the world through a process called teleconnections.
A strong El Niño has provided, on average, near to warmer conditions for our part of Ohio and Western Pennsylvania through the winter during strong El Niño years.
You can see in the image below that the northern part of the U.S. is typically warmer than normal during a strong El Niño winter. It is typically colder in the south.
El Niño’s influence on U.S. temperatures during WEAK episodes
A weak El Niño has generally resulted in colder-than-average winters for Northeastern Ohio and Western Pennsylvania.
The image below shows that the northern and eastern parts of the U.S. are typically colder than normal during a weak El Niño winter. The temperature is typically warmer than average in the west.
U.S. winter temperature during El Niño since 1950
The image below shows the temperature anomaly during El Niño events since 1950. They are listed as strong, moderate and weak El Niños.
The data shows that the winters of 2015-2016, 1982-1983, 1997-1998 and 1957-1958 are at the top of the image and listed as “strong” El Niño winters.
Three out of four strong El Niño winters were warmer than normal for Northeastern Ohio and Western Pennsylvania.
A moderate El Niño is split with four winters near/warmer than normal and four winters near/cooler than normal.
A weak El Niño favors a better chance for a cooler-than-normal winter for our part of the country. You can see in the image that eight of the 12 weak El Niño winters were cooler than normal. Only four weak El Niño winters were warmer than normal
Strong El Nino top 10 warm winters in Youngstown
The fourth warmest winter with an average temperature of 34.5°F took place during the winter of 1982-1983.
The fifth warmest winter with an average temperature of 34.4°F took place during the winter of 1997-1998.
The 10th warmest winter with an average temperature of 33.5°F took place during the winter of 2015-2016.
Strong El Niño top 10 least snowy winters in Youngstown
The sixth least snowy winter on record took place during the winter of 1997-1998 with a snowfall total of 19.8 inches of snow from December through February.
The ninth least snowy winter on record took place during the winter of 1997-1998 with a snowfall total of 21.7 inches of snow from December through February.
El Niño’s influence on U.S. precipitation during WEAK episodes
A weak El Niño has proven to provide, on average, near normal winter precipitation conditions for our part of Ohio and Western Pennsylvania.
You can see in the image below that the middle part of the U.S. through the Mississippi River region is typically drier than normal during a weak El Niño winter. It is typically wetter in the west.
El Nino’s influence on U.S. precipitation during STRONG episodes
A strong El Niño has proven to provide, on average, below normal winter precipitation conditions for our part of Ohio and Western Pennsylvania.
You can see in the image below that the southern part of the U.S. is typically wetter than normal during a strong El Niño winter. It is typically wetter on the west coast and drier in the northwest Rocky Mountains.
What will our winter be like in Youngstown based on El Niño only?
Long-range forecasting is a very challenging task. You can look at weather pattern influences like El Niño and La Niña to help guide your forecast, but these are not the only factors that influence a winter season. There are many other big pattern teleconnections that also influence our winter season.
If the winter forecast was strictly based on a strong El Niño, we could expect a warmer-than-normal winter with less precipitation than normal. This has happened in three out of the four most recent strong El Niño winters. However, one was not a warm winter.
Our region is also influenced by lake effect precipitation. This tends to increase our chances each winter to see slightly higher precipitation compared to areas not too far from home to our south and west.
In the end, if you based a winter forecast on only El Niño, the winter would have a higher chance of ending as a warmer and drier winter than normal.