Vermont's Changing Climate - Meteorological Impacts

VERMONT - With spring on Vermont's doorstep, many people across the state have been looking forward to the warmer weather. Given we had our fair share of snowstorms during this winter season, it may not seem like the climate in the state is trending warmer, but experts are warning otherwise. Scott Whittier is the Warning Coordination Meteorologist at the National Weather Service in Burlington. Having forecast the weather in the state since 1993, Scott has witnessed changes firsthand.

"The winters especially are not as severe as they used to be. We still have our severe days and severe stretches. But, the average temperature since I've been here basically in the last 25 to 30 years here in the Champlain Valley for Burlington, has risen about four degrees Fahrenheit for the winter, three degrees for daily highs, and about five degrees for daily lows. Across the rest of the state, it's been closer to one to two degrees change over the past 30 years."

These changes can have a significant impact on the area, especially since temperatures during a good portion of the winter average around the freezing mark.

"The number of sub-zero mornings here in the Champlain Valley has drastically changed, going from an average of 26 to 30, where it's down to almost half, between 15 to 18... There have been similar trends across the rest of the state, not to the same degree of change. Those real sub-freezing mornings there in the Northeast Kingdom of 20 to 25 degrees below zero are not as frequent as they were when I went to LSC."

The warming trend occurring across the state has also led to an adjustment to the 30-year climatological averages used by the National Weather Service. Every ten years the weather service will update this database of averages with the most recent 30-year period. Last year the weather service was still using the data from 1981 to 2010. The newly released data (1991-2020) now includes the warming trend that we've seen drastically increase over the past 10 years and has now factored that into the averages.

"Having the new and updated maps is more evidence to support that there is warming going on in our climate, especially here in Vermont. I don't know if everyone is aware that those new 30-year climate normals have been established, but it certainly shows the trends that people have been talking about for the past several decades. It shows that we are warming, and in some places that we're warming faster than what was originally predicted, especially in the northern climates."

As this warming trend continues, Vermont will see the impacts on the winter season. Warmer temperatures put at risk the industries that rely on cold temperatures during the winter months for their business. Action continues to be considered at national levels, but delays have caused states to put their own plans in place. In the next part of this series, we'll look at the Vermont Climate Assessment to further investigate the impacts that are being left across the state because of this, as well as some solutions the legislature is trying to put in place with the assessment.