Southold climate

Southold Weather in September

NOAA 1991-2020 normals for Mattituck, 11.1 km from Southold

Average highs run from 79°F on September 1 to 69°F on September 30, and lows from 62°F to 52°F. Normal precipitation for the month is 3.79 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 Southold, in °F, with the record for each date.20406080100151015202530
  • Normal low
  • Normal high
  • Record high
  • Record low

September at a glance

Average high
74°F
Average low
57°F
Precipitation
3.79 in
Record high
94°FSep 2, 1953
Record low
35°FSep 25, 1963
Chance of a freeze
0%
Daylight
13 h 06 min to 11 h 48 min
Cloud cover
53%
Humidity
78%
Dew point
60°F
Wind
9.8 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 179°F62°F93°F 201046°F 19860%
Sep 279°F61°F94°F 195344°F 19910%
Sep 378°F61°F90°F 197344°F 20170%
Sep 478°F61°F89°F 197344°F 20170%
Sep 578°F60°F90°F 198345°F 19870%
Sep 678°F60°F91°F 198345°F 19890%
Sep 777°F60°F93°F 198341°F 19380%
Sep 877°F59°F91°F 202344°F 19840%
Sep 977°F59°F88°F 195940°F 19860%
Sep 1076°F59°F90°F 198341°F 19380%
Sep 1176°F58°F93°F 193141°F 19950%
Sep 1276°F58°F88°F 196143°F 19950%
Sep 1375°F58°F89°F 200543°F 19670%
Sep 1475°F57°F85°F 200543°F 19920%
Sep 1575°F57°F88°F 200537°F 19860%
Sep 1674°F57°F84°F 194139°F 19830%
Sep 1774°F56°F84°F 199140°F 19840%
Sep 1874°F56°F82°F 199237°F 19590%
Sep 1973°F56°F85°F 196737°F 19840%
Sep 2073°F55°F86°F 198340°F 19820%
Sep 2173°F55°F82°F 198939°F 19560%
Sep 2272°F54°F89°F 198036°F 19620%
Sep 2372°F54°F88°F 194141°F 19470%
Sep 2472°F54°F83°F 200938°F 19530%
Sep 2571°F53°F86°F 193035°F 19630%
Sep 2671°F53°F87°F 193035°F 19870%
Sep 2770°F53°F82°F 199835°F 19780%
Sep 2870°F52°F80°F 201735°F 19890%
Sep 2970°F52°F80°F 201036°F 19470%
Sep 3069°F52°F79°F 195236°F 20000%

Chance of rain

The chance of at least 0.01 inch of precipitation on each date at Southold, 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 6:16 AM, sunset 7:22 PM
September 30
sunrise 6:45 AM, sunset 6:33 PM

Every day of September: sun and moon

Other months

Sources

Normals: NOAA NCEI U.S. Climate Normals, 1991-2020, station USC00305142 (Mattituck), public domain. Records: NOAA GHCN-Daily, station USC00300889, 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.