What is the current water temperature at Lake Sunapee?

Current water temperature for Lake Sunapee is shown in the live forecast above. Most New Hampshire lakes have no public real-time water-temperature sensor, so we estimate from recent and forecast air-temperature trends weighted by the lake's depth (105ft maximum).

Where is Lake Sunapee located?

Lake Sunapee is in New Hampshire (Sullivan County), with public access near Sunapee, Newbury, New London. Surface area is 4,085 acres.

How deep is Lake Sunapee?

Lake Sunapee's maximum depth is 105 feet. Deeper lakes carry more thermal inertia and warm more slowly through summer; shallower lakes track the air temperature faster.

New Hampshire · Sullivan County

Lake Sunapee

Sunapee · Newbury · New London

Loading live conditions for Lake Sunapee…

Surface area4,085acres

Max depth105feet

CountySullivan

Data sourceEWMA modelAir-temp trend

Things to do

Tours & activities on Lake Sunapee

Boat cruises, fishing trips, kayak rentals, and guided adventures from local operators.

Browse activities on Viator

Places to stay

Lake houses & rentals

Vacation rentals right on the water.

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"Crystal-clear, deep, and a popular weekend destination from Boston. Sunapee has a postcard-perfect main beach, a steamboat tour, and consistent water clarity that makes it a top swim/snorkel lake in NH."

Seasonal pattern

When does Lake Sunapee warm up?

Lake Sunapee (max depth 105ft) typically reaches swim-comfortable surface temperatures (65°F+) by early to mid-June in New Hampshire. The live forecast above shows current conditions.

Field notes

About Lake Sunapee

No public real-time sensor; surface temperature is modeled
Clear water and a maintained main beach

Surface area: 4,085 acres
Max depth: 105 ft
County: Sullivan
Water data: Modeled estimate from air-temp trends