Groton climate

Groton Weather in May

NOAA 1991-2020 normals for Andover #2, 15.5 km from Groton

Average highs run from 63°F on May 1 to 73°F on May 31, and lows from 39°F to 52°F. Normal precipitation for the month is 3.19 in.

May day by day

The normal high and low for each date, and the record, in °F.

Normal daily high and low temperature at Groton, in °F, with the record for each date.020406080100120151015202530
  • Normal low
  • Normal high
  • Record high
  • Record low

May at a glance

Average high
68°F
Average low
46°F
Precipitation
3.19 in
Record high
101°FMay 27, 2018
Record low
20°FMay 3, 2013
Chance of a freeze
68%
Days of 90°F or more
0.6
Daylight
14 h 19 min to 15 h 25 min
Cloud cover
65%
Humidity
62%
Dew point
43°F
Wind
11.9 mph

Every day of the month

A wet day has at least 0.01 inch of precipitation; snow means at least 0.1 inch of snowfall.

DateNormal highNormal lowRecord highRecord lowChance wetChance of snow
May 163°F39°F84°F 202126°F 2026
May 263°F40°F89°F 201526°F 2013
May 363°F40°F78°F 202320°F 2013
May 464°F41°F81°F 201827°F 2021
May 564°F41°F88°F 201630°F 2026
May 665°F42°F91°F 201632°F 2019
May 765°F42°F87°F 201725°F 2019
May 865°F42°F80°F 202530°F 2020
May 966°F43°F83°F 202534°F 2019
May 1066°F43°F86°F 202527°F 2019
May 1166°F44°F90°F 202529°F 2020
May 1267°F44°F91°F 202525°F 2013
May 1367°F45°F91°F 201333°F 2014
May 1468°F45°F88°F 202529°F 2016
May 1568°F46°F83°F 201727°F 2014
May 1668°F46°F90°F 201827°F 2014
May 1769°F47°F93°F 201230°F 2014
May 1869°F47°F92°F 201233°F 2015
May 1969°F47°F82°F 202132°F 2015
May 2070°F48°F80°F 201432°F 2019
May 2170°F48°F81°F 202335°F 2017
May 2270°F49°F88°F 201231°F 2022
May 2371°F49°F87°F 201638°F 20250%
May 2471°F50°F91°F 201837°F 20170%
May 2571°F50°F93°F 201838°F 20240%
May 2672°F50°F97°F 201838°F 20120%
May 2772°F51°F101°F 201840°F 20210%
May 2872°F51°F90°F 202635°F 20210%
May 2973°F51°F89°F 201837°F 20120%
May 3073°F52°F90°F 201433°F 20120%
May 3173°F52°F89°F 201836°F 20170%

Chance of rain

The chance of at least 0.01 inch of precipitation on each date at Groton, in percent, and of at least 0.1 inch of snowfall.00.21102030
  • Chance of a wet day
  • Chance of snowfall

Sunrise and sunset

Times for 2026, local time (CDT).

May 1
sunrise 6:20 AM, sunset 8:39 PM
May 31
sunrise 5:48 AM, sunset 9:13 PM

Every day of May: sun and moon

Other months

Sources

Normals: NOAA NCEI U.S. Climate Normals, 1991-2020, station USC00390120 (Andover #2), public domain. Records: NOAA GHCN-Daily, station USC00390022, every year on file, quality-flagged values removed. Cloud, humidity, wind and sunshine: NASA POWER (MERRA-2, CERES and GEWEX SRB), 1991-2020. The data was obtained from the National Aeronautics and Space Administration (NASA) Langley Research Center's Prediction Of Worldwide Energy Resources (POWER) project funded through the NASA Earth Science Division: POWER Daily API v2, accessed 2026-09-25. Sun and moon: computed with the NOAA solar equations and Meeus.