September
Other strong months: June and August
United States · 1991–2020
For Dupont, September has the most comfortable weather in our climate comparison. Typical daytime highs are 26.1°C, nights average 9.3°C, and rainfall totals about 33 mm. Figures use measured 1991–2020 normals from the nearest eligible NOAA station.
Other strong months: June and August
Other strong months: May and September
Make the answer personal
Set the daytime temperature and rainfall you are comfortable with. We will show only the months that meet every choice, using the measured 1991–2020 averages below.
4 months fit your choices for Dupont
The lowest comfort score is 5 out of 100. January and December share that score. In January, that is mainly because days reach only 7.5°C, 16° below the 24°C the score treats as ideal, and nights drop to -7.7°C.
Quick answers
These answers come from the same measured monthly climate record shown on this page.
September is the strongest all-round choice in our temperature-and-rainfall comparison, with a typical daytime high of 26.1°C and 33 mm of rain.
July is hottest in this record, with a typical daytime high of 31.8°C and a night-time low of 15.4°C.
January and December have the lowest monthly rainfall total at 12 mm.
No. These are long-term measured averages from 1991–2020. Check a current forecast before you travel.
Month by month
The bars combine daytime temperature, night-time temperature and rainfall. The figures are measured historical averages, not a forecast for a particular trip.
| Month | Day | Night | Rain | Wet days | Daylight | Comfort | Coverage |
|---|---|---|---|---|---|---|---|
| January | 7.5°C | -7.7°C | 12 mm | 3.6 | 9 h 38 | 5 | Strong coverage |
| February | 8.1°C | -6.8°C | 14 mm | 3.8 | 10 h 38 | 8 | Strong coverage |
| March | 13°C | -2.3°C | 28 mm | 4.4 | 11 h 49 | 31 | Strong coverage |
| April | 16.4°C | 1.3°C | 43 mm | 6.2 | 13 h 12 | 46 | Strong coverage |
| May | 21.5°C | 6.6°C | 58 mm | 7.6 | 14 h 21 | 69 | Strong coverage |
| June | 28.3°C | 11.9°C | 43 mm | 6.1 | 14 h 59 | 76 | Strong coverage |
| July | 31.8°C | 15.4°C | 54 mm | 6.1 | 14 h 44 | 68 | Strong coverage |
| August | 30.4°C | 14.2°C | 47 mm | 5.6 | 13 h 44 | 73 | Strong coverage |
| September | 26.1°C | 9.3°C | 33 mm | 4.6 | 12 h 24 | 81 | Strong coverage |
| October | 18.7°C | 2.3°C | 25 mm | 3.8 | 11 h 05 | 59 | Strong coverage |
| November | 12.1°C | -3.4°C | 18 mm | 3.9 | 9 h 55 | 27 | Strong coverage |
| December | 7.2°C | -7.7°C | 12 mm | 3.2 | 9 h 21 | 5 | Strong coverage |
What has changed
Each bar shows the difference between the 2011–2025 average daytime high and the 1961–1990 average for the same month at the same station. A blank month does not have enough older observations for a reliable comparison.
| Month | Record high | Record low | Wettest day | Wettest / driest month | Years |
|---|---|---|---|---|---|
| January | 23.3°C28 Jan 2015 | -31.7°C11 Jan 1963 | 23 mm8 Jan 1962 | 37 mm1948 · driest 0 mm in 2003 | 79 |
| February | 28.3°C11 Feb 2017 | -31.7°C1 Feb 1951 | 26 mm19 Feb 1953 | 52 mm2015 · driest 0 mm in 2026 | 79 |
| March | 30.6°C21 Mar 2026 | -23.3°C5 Mar 1948 | 79 mm19 Mar 2003 | 122 mm2003 · driest 0 mm in 2012 | 79 |
| April | 32.2°C30 Apr 1992 | -18.9°C2 Apr 1975 | 83 mm13 Apr 1967 | 136 mm1999 · driest 1 mm in 1963 | 79 |
| May | 35.6°C30 May 2003 | -5.6°C2 May 1954 | 84 mm12 May 2023 | 186 mm1957 · driest 2 mm in 1974 | 78 |
| June | 40.0°C29 Jun 2018 | -1.1°C2 Jun 1951 | 80 mm11 Jun 1970 | 187 mm2015 · driest 1 mm in 2006 | 79 |
| July | 40.0°C21 Jul 2005 | 6.1°C7 Jul 1952 | 97 mm19 Jul 1997 | 178 mm1998 · driest 4 mm in 2008 | 78 |
| August | 38.9°C1 Aug 2002 | 5.0°C23 Aug 1964 | 97 mm19 Aug 2004 | 149 mm1979 · driest 2 mm in 1960 | 78 |
| September | 37.2°C9 Sep 2022 | -8.3°C29 Sep 1985 | 99 mm12 Sep 2013 | 189 mm2013 · driest 0 mm in 1992 | 78 |
| October | 31.7°C1 Oct 2023 | -16.1°C13 Oct 1969 | 40 mm18 Oct 1960 | 106 mm1969 · driest 1 mm in 1962 | 78 |
| November | 27.8°C3 Nov 2025 | -23.3°C13 Nov 2014 | 24 mm20 Nov 1979 | 68 mm1991 · driest 0 mm in 1949 | 78 |
| December | 24.4°C23 Dec 2025 | -31.7°C22 Dec 1990 | 51 mm24 Dec 1982 | 72 mm1973 · driest 0 mm in 2002 | 78 |
| Month | Days 25°C+ | Days 30°C+ | Frost nights | Heavy rain (10 mm+) | Snow days |
|---|---|---|---|---|---|
| January | 0 | 0 | 30 | <1 | 5 |
| February | 0 | 0 | 26 | <1 | 5 |
| March | <1 | 0 | 22 | <1 | 5 |
| April | 3 | 0 | 12 | 1 | 4 |
| May | 11 | 3 | 2 | 2 | <1 |
| June | 23 | 13 | 0 | 1 | 0 |
| July | 29 | 23 | 0 | 1 | 0 |
| August | 28 | 20 | 0 | 1 | 0 |
| September | 20 | 9 | <1 | <1 | <1 |
| October | 8 | <1 | 9 | <1 | 2 |
| November | <1 | 0 | 24 | <1 | 5 |
| December | 0 | 0 | 30 | <1 | 5 |
| Month | Dry days reaching 20°C | Wet days | Days with heavy rain | Weeks with 3+ wet days | Typical high by year |
|---|---|---|---|---|---|
| January | 1% | 11% | <1% | 5% | 3.0–9.5°C |
| February | 4% | 13% | <1% | 8% | 4.6–11.9°C |
| March | 15% | 17% | 2% | 13% | 8.2–15.4°C |
| April | 35% | 20% | 4% | 18% | 13.1–19.2°C |
| May | 57% | 24% | 6% | 28% | 18.8–23.9°C |
| June | 78% | 20% | 4% | 18% | 24.5–30.8°C |
| July | 80% | 20% | 5% | 19% | 29.7–33.4°C |
| August | 82% | 17% | 3% | 12% | 28.3–32.1°C |
| September | 78% | 14% | 3% | 11% | 23.4–28.3°C |
| October | 51% | 11% | 2% | 6% | 16.2–21.5°C |
| November | 15% | 13% | 2% | 7% | 8.5–15.1°C |
| December | 2% | 11% | <1% | 6% | 4.3–10.0°C |
A dry day reaching 20°C records under 1 mm of rain. A wet day records at least 1 mm, while a heavy-rain day records at least 10 mm. The weekly figure is the share of seven-day periods containing three or more wet days. The final column shows the middle 80% of average daytime highs recorded for that month in individual years; a wider range means conditions have varied more from one year to another.
The evidence behind this page
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The weather comparison for Dupont is based on climate evidence, not payments from travel companies. Flight, accommodation and activity links will be clearly labelled when they are added; there are no booking offers on this page today.
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