Riverdale climate

Riverdale Weather in September

NOAA 1991-2020 normals for Wanaque Raymond Dam, 5.7 km from Riverdale

Average highs run from 81°F on September 1 to 70°F on September 30, and lows from 61°F to 50°F. Normal precipitation for the month is 3.95 in over about 9 wet days.

September day by day

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

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

September at a glance

Average high
76°F
Average low
56°F
Precipitation
3.95 in
Record high
96°FSep 7, 2023
Record low
37°FSep 29, 2000
Chance of a freeze
0%
Days of 90°F or more
0.8
Daylight
13 h 06 min to 11 h 48 min
Cloud cover
57%
Humidity
73%
Dew point
55°F
Wind
4.3 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 181°F61°F95°F 201050°F 201727%0%
Sep 280°F61°F94°F 201046°F 201727%0%
Sep 380°F60°F93°F 201551°F 200127%0%
Sep 480°F60°F92°F 200852°F 202427%0%
Sep 580°F60°F93°F 202349°F 200027%0%
Sep 679°F60°F95°F 201845°F 200027%0%
Sep 779°F59°F96°F 202347°F 200027%0%
Sep 879°F59°F95°F 201549°F 200027%0%
Sep 979°F59°F93°F 200248°F 201727%0%
Sep 1078°F58°F93°F 201649°F 201727%0%
Sep 1178°F58°F93°F 201347°F 201227%0%
Sep 1278°F58°F91°F 200546°F 200627%0%
Sep 1377°F57°F93°F 200546°F 200227%0%
Sep 1477°F57°F92°F 201647°F 201427%0%
Sep 1576°F57°F90°F 202144°F 200127%0%
Sep 1676°F56°F87°F 201843°F 200727%0%
Sep 1776°F56°F86°F 201543°F 200727%0%
Sep 1875°F55°F86°F 202541°F 201327%0%
Sep 1975°F55°F86°F 202445°F 200827%0%
Sep 2075°F54°F84°F 201643°F 202027%0%
Sep 2174°F54°F86°F 201641°F 202027%0%
Sep 2274°F53°F90°F 201940°F 202028%0%
Sep 2373°F53°F93°F 201943°F 201428%0%
Sep 2473°F53°F92°F 201741°F 201328%0%
Sep 2573°F52°F90°F 201742°F 201228%0%
Sep 2672°F52°F88°F 200743°F 200028%0%
Sep 2772°F51°F88°F 201739°F 200029%0%
Sep 2871°F51°F87°F 202543°F 200029%0%
Sep 2971°F50°F82°F 201537°F 200029%0%
Sep 3070°F50°F82°F 202537°F 200029%0%

Chance of rain

The chance of at least 0.01 inch of precipitation on each date at Riverdale, in percent, and of at least 0.1 inch of snowfall.01020301102030
  • Chance of a wet day
  • Chance of snowfall

Sunrise and sunset

Times for 2026, local time (EDT).

September 1
sunrise 6:24 AM, sunset 7:30 PM
September 30
sunrise 6:53 AM, sunset 6:41 PM

Every day of September: sun and moon

Other months

Sources

Normals: NOAA NCEI U.S. Climate Normals, 1991-2020, station USC00289187 (Wanaque Raymond Dam), public domain. Records: NOAA GHCN-Daily, station USW00054743, 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.