Darien climate

Darien Weather in September

NOAA 1991-2020 normals for Delavan Wwtp, 5.4 km from Darien

Average highs run from 78°F on September 1 to 69°F on September 30, and lows from 56°F to 46°F. Normal precipitation for the month is 3.74 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 Darien, 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
51°F
Precipitation
3.74 in
Record high
96°FSep 2, 2000
Record low
28°FSep 23, 1995
Chance of a freeze
16%
Days of 90°F or more
1.6
Daylight
13 h 09 min to 11 h 47 min
Cloud cover
51%
Humidity
75%
Dew point
54°F
Wind
9.2 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 178°F56°F94°F 201240°F 20090%
Sep 278°F55°F96°F 200043°F 20090%
Sep 378°F55°F92°F 199943°F 19870%
Sep 478°F55°F94°F 202340°F 19970%
Sep 577°F55°F94°F 201238°F 19880%
Sep 677°F54°F95°F 199039°F 19880%
Sep 777°F54°F92°F 201641°F 20250%
Sep 877°F54°F91°F 200341°F 20240%
Sep 976°F53°F91°F 200241°F 19950%
Sep 1076°F53°F94°F 201342°F 19950%
Sep 1176°F53°F95°F 201337°F 19930%
Sep 1276°F53°F91°F 200539°F 19930%
Sep 1375°F52°F91°F 200538°F 20140%
Sep 1475°F52°F91°F 199837°F 20140%
Sep 1575°F52°F89°F 202434°F 20070%
Sep 1674°F51°F90°F 202435°F 20070%
Sep 1774°F51°F91°F 198838°F 19990%
Sep 1874°F51°F91°F 201839°F 19990%
Sep 1973°F50°F88°F 200736°F 20120%
Sep 2073°F50°F91°F 202133°F 19910%
Sep 2173°F50°F93°F 201732°F 19910%
Sep 2272°F49°F92°F 201733°F 19890%
Sep 2372°F49°F95°F 201728°F 19950%
Sep 2472°F49°F95°F 201729°F 19950%
Sep 2571°F48°F93°F 201733°F 19950%
Sep 2671°F48°F94°F 201732°F 19890%
Sep 2770°F47°F90°F 199829°F 19910%
Sep 2870°F47°F88°F 202130°F 19910%
Sep 2969°F47°F84°F 202530°F 19910%
Sep 3069°F46°F89°F 202529°F 19930%

Chance of rain

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

September 1
sunrise 6:20 AM, sunset 7:29 PM
September 30
sunrise 6:51 AM, sunset 6:38 PM

Every day of September: sun and moon

Other months

Sources

Normals: NOAA NCEI U.S. Climate Normals, 1991-2020, station USC00472051 (Delavan Wwtp), public domain. Records: NOAA GHCN-Daily, station USC00470045, 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.