Dennis Port climate

Dennis Port Weather in September

NOAA 1991-2020 normals for W Harwich, 1.2 km from Dennis Port

Average highs run from 75°F on September 1 to 67°F on September 30, and lows from 60°F to 52°F. Normal precipitation for the month is 3.93 in.

September day by day

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

Normal daily high and low temperature at Dennis Port, in °F, with the record for each date.20406080100151015202530
  • Normal low
  • Normal high
  • Record high
  • Record low

September at a glance

Average high
71°F
Average low
57°F
Precipitation
3.93 in
Record high
90°FSep 1, 2010
Record low
37°FSep 20, 2019
Chance of a freeze
0%
Daylight
13 h 07 min to 11 h 48 min
Cloud cover
57%
Humidity
84%
Dew point
59°F
Wind
13.9 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
Sep 175°F60°F90°F 201051°F 19990%
Sep 275°F60°F84°F 201047°F 20170%
Sep 375°F60°F83°F 201553°F 20090%
Sep 475°F60°F85°F 202051°F 19970%
Sep 574°F60°F87°F 202349°F 19970%
Sep 674°F59°F87°F 202345°F 20000%
Sep 774°F59°F90°F 202344°F 20000%
Sep 874°F59°F86°F 201552°F 20030%
Sep 973°F59°F85°F 202347°F 20030%
Sep 1073°F58°F84°F 202347°F 20030%
Sep 1173°F58°F87°F 202249°F 20050%
Sep 1272°F58°F83°F 202348°F 20020%
Sep 1372°F58°F82°F 202347°F 20250%
Sep 1472°F57°F81°F 202448°F 20140%
Sep 1572°F57°F84°F 200845°F 20010%
Sep 1671°F57°F78°F 201544°F 20010%
Sep 1771°F56°F79°F 201544°F 20130%
Sep 1871°F56°F80°F 201645°F 20130%
Sep 1970°F56°F77°F 200544°F 20140%
Sep 2070°F56°F77°F 202337°F 20190%
Sep 2170°F55°F79°F 201946°F 20250%
Sep 2269°F55°F78°F 200241°F 19970%
Sep 2369°F55°F82°F 200545°F 19980%
Sep 2469°F54°F78°F 200942°F 19980%
Sep 2568°F54°F81°F 201143°F 20050%
Sep 2668°F54°F82°F 201143°F 20160%
Sep 2768°F53°F78°F 201445°F 20150%
Sep 2867°F53°F77°F 201546°F 20000%
Sep 2967°F53°F77°F 201039°F 20000%
Sep 3067°F52°F76°F 201038°F 20000%

Chance of rain

The chance of at least 0.01 inch of precipitation on each date at Dennis Port, 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).

September 1
sunrise 6:07 AM, sunset 7:14 PM
September 30
sunrise 6:36 AM, sunset 6:24 PM

Every day of September: 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 USW00094624, 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.