Historical Trends of Mountain Weather

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Regionally and globally temperatures are on the rise but what is happening in the mountains of the Northeast? 

A recent analysis by the Mount Washington Observatory (MWO) of their long-term temperature records from the summit of Mount Washington shows a significant increase in average annual temperature on the summit from 1935-2003. The trends are even more pronounced in the winter and spring with increases of 0.71 °C and 0.80 °C respectively over this time period.*  Other regional studies have also shown that winters in the region are warming, on average at 3 times the rate of summers. The warmest year on the summit and globally was 1998.

The graph below shows average temperatures for the summit of Mount Washington by season or annually and the lines indicate a linear trend fit to the data. Use the radio buttons along the right to change the data in the graph. Note that the scale may changes with different selections. The table at the bottom shows the change in temperature over the period of record as determined by the linear trend line.