It’s too early to tell whether April snow in Portland is linked to climate change, scientists say

This week’s rare snowstorm could be an indication of climate change, but climate scientists say it’s too early to tell, as global warming trends make this event unlikely to be related.

According to data from the National Weather Service, snow was recorded in Portland at least six times in April according to data dating back as far as 1872.

Oregon’s state climatologist Larry O’Neill said these late-season snowstorms have gotten less frequent as the climate gets warmer, but Monday’s snowfall should not be considered an extreme event, despite Portland temperatures reaching into the mid 70s last week.

The snowstorm was “typical weather variability and not any sign of climate change,” O’Neill said. “I think the real story here is that we used to get snow more often in April in Portland and now we don’t.”

The snowstorm in Southwest Washington and Western Oregon At least one inch of snowPortland Metro Area. Portland International Airport, which is located in the National Weather ServiceIn 1940, the first snowfall and stick recorded by the office was recorded. The snowfall reached as high as 125 feet in the Portland metro area and Southwest Washington. 11 inches in some places.

But data from the National Weather Service’s previous downtown Portland officeIt was found that at least six occasions in the past 100 years were snowfalls occurred during April.

On April 1, 1936, Portland saw just over 5 inches of snow. On April 7, 1933, an inch and a quarter of a inch of snow was also recorded. In 1901, 1895, and 1903 there were also three cases where a tenth inch of snow was recorded in April.

O’Neill, who directs the Oregon Climate Service and works as an associate professor in Oregon State University’s College of Earth, Ocean and Atmospheric Sciences, said Monday’s snowstorm was not unprecedented but it was unusual in part because lowland snow is becoming less frequent as the climate is warming.

“Some people are saying, ‘Oh, extreme events happen more often under a changing climate.’ And some extreme events it is true, but this, I wouldn’t categorize as an extreme event, and it’s definitely not unprecedented,” he said.

O’Neill said lowland snow is typical during “La Niña,” a weather pattern that occurs in the Pacific Ocean that creates and shifts cooler temperatures up north during the winter while the south experiences warmer drought-like conditions. Lowland snow conditions could also be spotty as some areas will see snow that doesn’t stick.

Historically, O’Neill said, if the weather station did not get any snow, and other parts of the city or region did, it would not get recorded as a snow day since it did not occur where the National Weather Service has its official equipment.

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Climatologists in Oregon and Washington said the additional precipitation from this week’s storm Drought conditions can be improved, but not eliminatedAll over the Northwest

Paul Loikith from Portland State University is an associate professor in geography. He said that the snowstorm does have a connection to climate change, as spring weather has warmed in the past 80 years.

“It’s kind of in the opposite direction of the way the statistics are going as far as warming temperatures,” he said. “Aprils are warming in Portland. We’re seeing in general less extreme cold over time, and that’s projected to continue.”

Loikith said springtime is getting warmer and summer is the region’s fastest warming season, but warming is seen across every month of the year. Based on the trends and temperatures derived from current knowledge about how climate change is affecting this region, he said that it was unlikely that this snowstorm could be attributed to climate changes.

Loikith said that until a proper analysis is done, there can’t be a definitive answer. Attributing the snowstorm to climate change could require running two weather models comparing the likelihood of this event occurring in a pre-industrial climate versus today’s climate.

“Weather is capable of a wide range of extremes, even in the absence of human activity,” Loikith said.

Loikith said a perfect example of an extreme weather event occurring because of climate change was last June’s heat dome event, as it aligns with warming trends in the region. Extreme weather events such as wildfires can also be attributed to warming temperatures.

“Those impacts we’ve already felt,” he said. “We can measure it. It’s clearly connected.”