September
September · May · October
United States · 1991–2020
September leads for comfortable weather in Lewisville: typically 26.3°C by day, 14.3°C at night, with 104 mm of rain. Based on measured 1991–2020 NOAA station history.
September · May · October
August · June · July
October · April · May
The weakest month is January, scoring 5 against September’s 77 — days reach only 9.2°C, 15° below the 24°C the score treats as ideal, and nights drop to -3.5°C.
Month by month
The bars show the comfort score. Day and night temperatures come from daily observed highs and lows; rain is the historical monthly estimate.
| Month | Day | Night | Rain | Wet days | Daylight | Comfort | Coverage |
|---|---|---|---|---|---|---|---|
| January | 9.2°C | -3.5°C | 93 mm | 8 | 9 h 57 | 5 | Strong coverage |
| February | 11.5°C | -2.3°C | 79 mm | 7.3 | 10 h 49 | 17 | Strong coverage |
| March | 16°C | 1.2°C | 100 mm | 8.5 | 11 h 51 | 35 | Strong coverage |
| April | 21.4°C | 6°C | 104 mm | 8.4 | 13 h 03 | 61 | Strong coverage |
| May | 25°C | 11.3°C | 101 mm | 9.5 | 14 h 03 | 75 | Strong coverage |
| June | 29°C | 16.2°C | 110 mm | 9.7 | 14 h 36 | 65 | Strong coverage |
| July | 30.7°C | 18.6°C | 116 mm | 10.5 | 14 h 23 | 53 | Strong coverage |
| August | 29.6°C | 17.8°C | 112 mm | 8.7 | 13 h 32 | 61 | Strong coverage |
| September | 26.3°C | 14.3°C | 104 mm | 7.3 | 12 h 22 | 77 | Strong coverage |
| October | 21.1°C | 7°C | 84 mm | 6.2 | 11 h 12 | 66 | Strong coverage |
| November | 15.5°C | 0.9°C | 82 mm | 6.5 | 10 h 12 | 37 | Strong coverage |
| December | 10.6°C | -2.1°C | 97 mm | 8.1 | 9 h 43 | 12 | Strong coverage |
What has changed
Each bar compares the 2011–2025 daytime average for that month against the same month in 1961–1990, measured at the same station. Months where the older record is too thin to compare are left blank.
| Month | Record high | Record low | Wettest day | Wettest / driest month | Years |
|---|---|---|---|---|---|
| January | 25.6°C31 Jan 2002 | -22.2°C21 Jan 1985 | 71 mm10 Jan 2024 | 185 mm2024 · driest 22 mm in 1981 | 69 |
| February | 27.8°C26 Feb 1977 | -20.0°C20 Feb 2015 | 99 mm7 Feb 2020 | 224 mm2020 · driest 14 mm in 1978 | 69 |
| March | 31.7°C12 Mar 1990 | -14.4°C15 Mar 1993 | 108 mm20 Mar 2003 | 288 mm1975 · driest 20 mm in 2006 | 69 |
| April | 34.4°C25 Apr 1960 | -8.3°C8 Apr 1985 | 96 mm24 Apr 2017 | 226 mm1958 · driest 10 mm in 2002 | 69 |
| May | 36.1°C19 May 1962 | -1.7°C2 May 1963 | 87 mm15 May 2012 | 225 mm2017 · driest 13 mm in 2007 | 69 |
| June | 40.0°C30 Jun 1959 | 3.9°C12 Jun 1972 | 137 mm21 Jun 1972 | 218 mm1989 · driest 1 mm in 1986 | 69 |
| July | 40.6°C8 Jul 1977 | 8.3°C2 Jul 1988 | 102 mm2 Jul 1987 | 289 mm2022 · driest 24 mm in 2017 | 69 |
| August | 40.0°C18 Aug 1988 | 6.7°C30 Aug 1986 | 167 mm10 Aug 1970 | 282 mm1970 · driest 21 mm in 1982 | 68 |
| September | 37.2°C10 Sep 1983 | 0.0°C30 Sep 1967 | 143 mm8 Sep 1977 | 279 mm1979 · driest 3 mm in 2019 | 68 |
| October | 35.6°C3 Oct 2019 | -6.7°C30 Oct 1965 | 114 mm11 Oct 1990 | 319 mm1990 · driest 0 mm in 2000 | 68 |
| November | 30.6°C2 Nov 1974 | -13.3°C25 Nov 1970 | 104 mm12 Nov 2020 | 203 mm2020 · driest 11 mm in 2012 | 69 |
| December | 26.7°C8 Dec 1998 | -17.8°C13 Dec 1962 | 99 mm28 Dec 1958 | 191 mm1961 · driest 7 mm in 1965 | 69 |
| Month | Days 25°C+ | Days 30°C+ | Frost nights | Heavy rain (10 mm+) | Snow days |
|---|---|---|---|---|---|
| January | 0 | 0 | 23 | 3 | 1 |
| February | <1 | 0 | 20 | 3 | <1 |
| March | 3 | 0 | 15 | 4 | <1 |
| April | 10 | 1 | 4 | 3 | 0 |
| May | 18 | 4 | <1 | 3 | 0 |
| June | 27 | 13 | 0 | 4 | 0 |
| July | 30 | 20 | 0 | 4 | 0 |
| August | 29 | 15 | 0 | 3 | 0 |
| September | 20 | 6 | 0 | 4 | 0 |
| October | 7 | <1 | 3 | 3 | 0 |
| November | <1 | 0 | 16 | 3 | 0 |
| December | <1 | 0 | 22 | 4 | <1 |
| Month | Warm & dry days | Wet days | Washouts | Week with 3+ wet days | Daytime mean has ranged |
|---|---|---|---|---|---|
| January | 3% | 26% | 10% | 30% | 6.8–11.8°C |
| February | 8% | 27% | 10% | 30% | 8.3–14.2°C |
| March | 25% | 28% | 11% | 32% | 13.4–19.5°C |
| April | 53% | 27% | 10% | 30% | 19.8–24.6°C |
| May | 64% | 30% | 11% | 38% | 23.4–27.8°C |
| June | 69% | 31% | 11% | 36% | 27.5–31.2°C |
| July | 67% | 33% | 12% | 43% | 29.2–32.8°C |
| August | 72% | 28% | 10% | 33% | 28.6–32.3°C |
| September | 75% | 23% | 11% | 23% | 25.1–29.2°C |
| October | 58% | 20% | 9% | 20% | 19.4–23.8°C |
| November | 23% | 22% | 8% | 21% | 13.3–18.5°C |
| December | 5% | 26% | 11% | 28% | 7.9–13.5°C |
A warm and dry day reaches 20°C with under 1 mm of rain; a wet day gets 1 mm or more; a washout gets 10 mm or more. The week column is the share of seven-day stretches in that month, across the station’s whole daily record, that contained three or more wet days — the odds a week-long trip is rained on repeatedly, counted rather than modelled. The last column is the 10th to 90th percentile of that month’s daytime average across individual years: a narrow band means the average is what you will get, a wide one means the average is a midpoint between years that felt quite different.
The evidence behind this page