Beating the heat: How do the Adirondacks compare to NYC?

Unsurprisingly, when comparing summer temps in Adirondacks and NYC, Northern New York weather stations post cooler summer temps. Overnight lows show much greater differences

By Zachary Matson

The Adirondacks have long been a favorite summertime getaway for New York’s city dwellers, but just how much cooler is the Adirondack Park than sweltering New York City?

The University at Albany’s network of weather stations helps shed light on the temperature differences and shows just how varied temperatures within the park can be. Weather stations along the Lake Champlain shoreline in Essex and Ticonderoga, in fact, register average summer temperatures closer to those of New York City’s boroughs than the higher elevation stations in Old Forge and other reaches of the park, according to an analysis of Mesonet weather data stretching from the summer of 2016 to June of this year.

The map below shows the location of the Mesonet weather stations in the Adirondack Park and New York city, as well as average summertime highs and lows and the highest-recorded “feels like” temperature, a heat index measure.

New York City’s built-up urban environment induces an urban heat island effect, increasing daily high temperatures, sometimes to dangerous levels. The buildings, concrete and other human development absorbs and retains heat during the day, preventing a significant cooling overnight. Visitors to the Adirondacks, meanwhile, often enjoy cool nights and mornings, even during the hottest days of the year.

While the Mesonet data is not a long enough record to pinpoint warming trends, it does offer insight into the dynamics of temperature gradient between the city and the park during the summer, when a couple degrees of heat can be the difference between a hot day and a dangerously-hot day. The data also underscores how the urban heat effect is especially strong overnight. Over the eight years of data, there were over 200 summer days when the Indian Lake station recorded a higher daily maximum temperature than the Manhattan. But only once did Manhattan record a cooler overnight low than Indian Lake. So even when it’s hotter in the Adirondacks during the day, it’s almost surely cooler than the city overnight.

Temperatures in the Adirondacks do often match or exceed those in the city, and some Adirondack stations have recorded multiple days above 90 degrees, a mark scientists and health authorities caution poses heat-related risks. This chart shows the longest heat streaks of at least three days of high temperatures at or above 90 degrees in the city and Adirondacks over the past eight summers.