Weather on September 21
New Haven, CT
55 Years of Data
About This Date
September 21st in New Haven, CT typically brings pleasant fall weather, with average highs around 73°F and lows near 55°F. Over 54 years of records, the warmest September 21st was in 1980 (78°F average), while the coldest was 1993 (47°F) — a 31°F range across recorded history. Rain or other precipitation has occurred on about 30% of September 21st dates historically, with the wettest September 21st recording 1.65" of rain. Temperatures on this date have remained relatively stable over the past several decades.
Temperatures on this date have remained relatively stable over the past several decades.
Planning for September 21st in New Haven, CT? Great weather for outdoor activities. Consider bringing rain gear or an umbrella.
| Year | High | Low | Avg | Precip | Snow |
|---|---|---|---|---|---|
| 2026 | 72° | 57° | 64° | — | — |
| 2025 | 71° | 51° | 61° | — | — |
| 2024 | 74° | 63° | 68° | — | — |
| 2023 | 74° | 53° | 63° | — | — |
| 2022 | 77° | 57° | 67° | — | — |
| 2021 | 78° | 54° | 66° | — | — |
| 2020 | 68° | 43° | 55° | — | — |
| 2019 | 80° | 53° | 67° | — | — |
| 2018 | 74° | 67° | 70° | — | — |
| 2017 | 77° | 68° | 73° | — | — |
| 2016 | 85° | 61° | 73° | — | — |
| 2015 | 74° | 51° | 62° | — | — |
| 2014 | 79° | 67° | 73° | 1.36" | — |
| 2013 | 78° | 61° | 69° | — | — |
| 2012 | 70° | 54° | 62° | — | — |
| 2011 | 75° | 57° | 66° | — | — |
| 2010 | 71° | 47° | 59° | — | — |
| 2009 | 74° | 47° | 60° | — | — |
| 2008 | 76° | 46° | 61° | 0.01" | — |
| 2007 | 78° | 55° | 67° | — | — |
| 2006 | 68° | 48° | 58° | — | — |
| 2005 | 80° | 63° | 71° | — | — |
| 2004 | 76° | 49° | 62° | — | — |
| 2003 | 74° | 56° | 65° | — | — |
| 2002 | 80° | 69° | 75° | — | — |
| 2001 | 74° | 64° | 69° | 0.14" | — |
| 2000 | 77° | 50° | 64° | — | — |
| 1999 | 65° | 55° | 60° | 0.68" | — |
| 1997 | 85° | 42° | 63° | 0.02" | — |
| 1996 | 74° | 44° | 59° | — | — |
| 1995 | 72° | 55° | 63° | — | — |
| 1993coldest | 57° | 38° | 47° | 0.19" | — |
| 1992 | 72° | 48° | 60° | — | — |
| 1991 | 59° | 40° | 49° | — | — |
| 1990 | 69° | 50° | 60° | — | — |
| 1989 | 79° | 71° | 75° | 0.84" | — |
| 1988 | 76° | 68° | 72° | 0.54" | — |
| 1987 | 69° | 56° | 62° | — | — |
| 1986 | 67° | 59° | 63° | 0.25" | — |
| 1985 | 84° | 55° | 70° | — | — |
| 1984 | 75° | 58° | 66° | — | — |
| 1983 | 88° | 69° | 78° | — | — |
| 1982 | 60° | 50° | 55° | 0.6" | — |
| 1981 | 70° | 48° | 59° | — | — |
| 1980warmest | 87° | 68° | 78° | — | — |
| 1979 | 65° | 39° | 52° | 1.65" | — |
| 1978 | 74° | 52° | 63° | — | — |
| 1977 | 56° | 49° | 52° | 0.05" | — |
| 1976 | 78° | 61° | 69° | 0.13" | — |
| 1975 | 73° | 61° | 67° | 1.21" | — |
| 1974 | 77° | 64° | 71° | 0.85" | — |
| 1973 | 63° | 42° | 52° | — | — |
| 1972 | 62° | 51° | 57° | — | — |
| 1971 | 72° | 62° | 67° | 0.37" | — |
New Haven, CT Temperature Range by Month
Average monthly highs and lows. The shaded band shows the typical daily temperature range.
New Haven, CT Monthly Precipitation
Average rainfall and snowfall per month, in inches.
New Haven, CT Daily Temperature Calendar
Average daily high temperature for every day of the year. Each cell is the climatological mean for that calendar day across 55 years of NOAA data.
Best Time to Visit New Haven, CT
Most pleasant months in New Haven, CT: May, June, August, September.
What to expect on September 21st
This page shows what actually happened each year. For the odds — typical high and low, and how often it stays dry — see the climatological outlook for this date.
September 21st outlook →