CAPE COD — Sweltering summers — and higher electricity usage to cool homes — could become the norm in Cape Cod by mid-century, according to new data that calculates temperature extremes associated with climate change.

How hot could it get?

Falmouth is projected to get no days of 100-plus degree Fahrenheit temperatures by 2023, and that could increase to one in 30 years, according to data released Monday by the nonprofit First Street Foundation, which helps homeowners calculate property risks due to flooding, wildfires and extreme heat over 30 years, the length of a typical mortgage.

In the areas closer to the Bourne Bridge, projects show two days of 100-plus degree temperatures by 2023, with an increase to five in 30 years. Alternatively, the mid-Cape isn't projected to eclipse 100 degrees in 2023 or 2053.

Temperatures between 10 and 18 degrees above average are forecast this week for Washington, Oregon, Idaho and Montana, central California and central Nevada, according to AccuWeather.

Conservatively, average temperatures across the United States are expected to increase by 4.5 degrees Fahrenheit over the next 30 years. Also, because hotter temperatures increase the rate of water evaporation, Americans are likely to see warmer, stickier air over the next three decades, according to the First Street model.

Places that already have moist climates, including the Mid-Atlantic and Great Lakes regions, could feel the humidity more acutely, not only during the day, but into the nighttime, according to First Street

In the South, the number of triple-digit days could increase by 20 in places like Texas and Florida could see 70 days of triple-digit heat, The Washington Post analysis showed.

“We’re talking about taking summer, which is already hot, and expanding it for months,” Jaime González, director of the Houston Healthy Cities program for the Nature Conservancy in Texas, told The Washington Post. “That’s going to cause all sorts of disruptions to everyday life.”

Also, from the First Street model:

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