South Dennis climate

South Dennis Weather in May

NOAA 1991-2020 normals for W Harwich, 4.4 km from South Dennis

Average highs run from 57°F on May 1 to 66°F on May 31, and lows from 43°F to 53°F. Normal precipitation for the month is 3.50 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 South Dennis, in °F, with the record for each date.20406080100151015202530
  • Normal low
  • Normal high
  • Record high
  • Record low

May at a glance

Average high
62°F
Average low
48°F
Precipitation
3.50 in
Record high
89°FMay 25, 2007
Record low
27°FMay 7, 2001
Chance of a freeze
4%
Daylight
14 h 02 min to 14 h 59 min
Cloud cover
66%
Humidity
89%
Dew point
48°F
Wind
14.1 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 157°F43°F72°F 201029°F 20080%
May 257°F43°F83°F 200133°F 19990%
May 358°F44°F86°F 200135°F 20000%
May 458°F44°F86°F 200133°F 20030%
May 558°F44°F73°F 201031°F 20030%
May 659°F45°F71°F 202329°F 20010%
May 759°F45°F75°F 201527°F 20010%
May 859°F45°F71°F 202333°F 20060%
May 960°F46°F79°F 200034°F 20170%
May 1060°F46°F74°F 200134°F 20010%
May 1160°F46°F83°F 200431°F 20100%
May 1261°F47°F80°F 200135°F 20100%
May 1361°F47°F74°F 202332°F 20100%
May 1461°F47°F79°F 202232°F 19990%
May 1561°F48°F75°F 200434°F 19990%
May 1662°F48°F76°F 201735°F 19990%
May 1762°F48°F78°F 202638°F 20030%
May 1862°F49°F84°F 201738°F 20010%
May 1963°F49°F83°F 201736°F 20030%
May 2063°F49°F82°F 202637°F 20020%
May 2163°F50°F76°F 199836°F 20200%
May 2263°F50°F77°F 200938°F 20020%
May 2364°F50°F84°F 202139°F 20230%
May 2464°F51°F78°F 202437°F 20230%
May 2564°F51°F89°F 200740°F 20060%
May 2665°F51°F89°F 201042°F 20010%
May 2765°F52°F81°F 202141°F 20230%
May 2865°F52°F79°F 201642°F 20130%
May 2965°F52°F82°F 201840°F 20140%
May 3066°F53°F83°F 199837°F 20140%
May 3166°F53°F89°F 201339°F 20000%

Chance of rain

The chance of at least 0.01 inch of precipitation on each date at South Dennis, 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 (EDT).

May 1
sunrise 5:37 AM, sunset 7:39 PM
May 31
sunrise 5:09 AM, sunset 8:08 PM

Every day of May: sun and moon

Other months

Sources

Normals: NOAA NCEI U.S. Climate Normals, 1991-2020, station USC00199227 (W Harwich), public domain. Records: NOAA GHCN-Daily, station USW00094720, 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 2026-09-24. Sun and moon: computed with the NOAA solar equations and Meeus.