El Niño could lead to warmer, drier winter

By: Kevin Bunch | Roseville - Eastpointe Eastsider | Published December 2, 2015


This year’s El Niño event is one of the strongest in recorded history, and researchers believe it is increasing the likelihood of a winter that is both warmer and drier than usual.

El Niño is a periodic natural occurrence where warm water cycles around in the Pacific Ocean and reaches the surface. The increase in sea surface temperatures in turn impacts how storms and air pressure regions form and impacts global weather patterns — typically in the Northern Hemisphere’s winter months.

Jon Gottschalck, chief of the National Oceanic and Atmospheric Administration Climate Prediction Center’s operational prediction branch, said that while it is too early to tell how strong this El Niño event will end up, based on available data, it likely will end up being one of the “top three” ever recorded and affect the winter months even in Michigan.

“We’re favoring above-normal temperatures along much of the northern tier of the country, into the Great Lakes and the Northeast,” Gottschalck said. “The highest probabilities are across the northern Plains and the Great Lakes, where above-average temperatures are greater than a 50 percent probability.”

The average is based on all the 20th-century weather data compiled together. The U.S. has been monitoring and recording weather since 1880 in some parts of the country.

According to NOAA’s data, for the winter months of December through February, metro Detroit has a 50 to 60 percent probability of being warmer than it would on a given day. Northern Michigan could see an up to 65 percent probability of warmer weather during the same time period, Gottschalck added.

There is also a 40 to 50 percent probability that the same time period will be drier than average, Gottschalck said. In turn, the southern U.S. is expecting a lot more precipitation than usual, particularly along the border in California, Texas, Arizona and New Mexico, and on into the Gulf Coast.

Jim Noel, NOAA hydrologist with the National Weather Service, said that while these trends do not preclude bouts of cold weather or heavy winter storms, the winter months as a whole should be warmer and drier than usual — and certainly more than the past two winters.

Gottschalck said a strong El Niño effect, like the one being seen this year, can override other climate factors to some degree, though with so many variables, he cautioned that NOAA can only deal in probabilities.

“We expect El Niño is the primary driver (this year), but that doesn’t preclude other climate variability,” he said. “That’s why our forecasts are probabilistic; overall, beyond a few weeks, forecasting is quite a challenge.”

Gottschalck added that as El Niño develops more tropical rainstorm fronts, it should “push” the jet stream eastward, impacting drought and temperature conditions in the U.S.

The jet stream is a powerful wind current that has a major impact on climate events across the globe; rising temperatures in the Arctic have led to the polar jet stream warping in shape and bringing more severe weather patterns with it that have included California’s drought and Michigan’s cold, snowy winters the past few years.

Playing a factor in this winter is global warming; NOAA climate scientist Ahira Sanchez-Lugo announced in a press conference Nov. 19 that October 2015 globally was the warmest October on record, with 2015 on track to be the warmest year worldwide since the U.S. started recording weather.

“The only way that it would not break the record is if November and December temperature data was near the 20th-century average with departure (from the average) of zero,” Sanchez-Lugo said. “The last time that happened was February 1985, so we’re pretty confident it will be the warmest year on record.”

Sanchez-Lugo said areas like Australia, central Africa, Central America and northern South America experienced record warm temperatures in October, as did large portions of the Atlantic, Pacific and Indian oceans.

In the U.S., she said, the only state that saw cooler-than-average temperatures in October was Maine; the Northeast, Ohio Valley and East Coast all had close to average temperatures, while the rest of the country was warmer than average to varying degrees.

In total, Sanchez-Lugo said, the nation’s average temperature in October was 57.4 degrees — higher than the average. This made it the warmest October nationally since 1963, and the fourth-warmest in the U.S. since 1895.

Sanchez-Lugo said monthly temperatures globally have been increasing above average since 1980, and with a strong El Niño, that trend looks likely to continue during the winter months.

“We’re seeing signals of climate change,” she said. “Since 1980, the monthly temperatures have been increasing and will continue to increase. The strong El Niño has been giving this year an extra boost, for lack of a better word.”