New London, CT

Climate overview — based on NOAA 1991-2020 normals from GROTON NEW LONDON AP, CT US.

Dfa Hot-summer humid continental climate 7b USDA hardiness Zone 7b

Year-round temperatures (°F)

20° 40° 60° 80° J F M A M J J A S O N D
Avg high Avg low

Climate summary

New London has an annual average temperature of 51.4°F with about 39.3 inches of precipitation per year. The warmest month is July (average high 79.8°F), and the coldest is January (average low 23.3°F). September is typically the wettest month (3.83 in) and February the driest (2.20 in).

Pleasant months
4 / 12
avg high 65–80°F, low ≥ 50°F
Annual swing
41.5°F
warmest to coldest month
Heating need
5,334
Cooling need
450

Best time to visit New London

Full guide →

Climate change signal

All-time records →

176 of 366 (48.1%) of New London's all-time daily heat records have been set since 2015. If records were spread evenly across the station's history, only about 5% would fall in any given decade.

1990s
0
2000s
114
2010s
163
2020s
89

Bars: number of all-time daily heat records still standing that were set in each decade.

Monthly averages

Month Avg High Avg Low Avg Temp Precipitation Snow Rainy days
January 38.3°F 23.3°F 30.8°F 2.68 in 9
February 40.2°F 24.6°F 32.4°F 2.20 in 8
March 46.6°F 30.7°F 38.6°F 3.82 in 9
April 56.2°F 39.1°F 47.6°F 3.58 in 11
May 64.8°F 48.8°F 56.8°F 3.31 in 12
June 73.8°F 58.2°F 66.0°F 3.30 in 11
July 79.8°F 64.8°F 72.3°F 3.24 in 10
August 79.2°F 63.8°F 71.5°F 3.32 in 10
September 73.5°F 56.9°F 65.2°F 3.83 in 9
October 63.2°F 45.6°F 54.4°F 3.66 in 10
November 53.3°F 36.8°F 45.1°F 3.24 in 9
December 43.9°F 29.0°F 36.5°F 3.13 in 10

Climate twins of New London

Why these? →

The most climatically similar US cities at least 140 miles away (by monthly temperature + precipitation pattern).

Frost dates
Last spring / first fall frost
All-time records
Hottest, coldest, wettest
Planting calendar
What to plant, and when

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