September
September · June · August
United States · 1991–2020
September leads for comfortable weather in Henderson: typically 25.2°C by day, 11.3°C at night, with 75 mm of rain. Based on measured 1991–2020 NOAA station history.
September · June · August
August · July · June
October · September · May
The weakest month is January, scoring 5 against September’s 81 — days reach only 1.6°C, 22° below the 24°C the score treats as ideal, and nights drop to -9.9°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 | 1.6°C | -9.9°C | 18 mm | 3.1 | 9 h 33 | 5 | Good coverage |
| February | 4.3°C | -7.3°C | 21 mm | 3.1 | 10 h 35 | 5 | Good coverage |
| March | 10.3°C | -2.6°C | 44 mm | 5.5 | 11 h 49 | 20 | Good coverage |
| April | 16.6°C | 3.3°C | 77 mm | 7.3 | 13 h 14 | 45 | Good coverage |
| May | 22.2°C | 10.1°C | 132 mm | 10.3 | 14 h 26 | 65 | Good coverage |
| June | 27.6°C | 15.6°C | 118 mm | 7.8 | 15 h 05 | 71 | Good coverage |
| July | 30.1°C | 18.1°C | 95 mm | 8.2 | 14 h 49 | 61 | Good coverage |
| August | 29°C | 17°C | 94 mm | 7.4 | 13 h 48 | 68 | Good coverage |
| September | 25.2°C | 11.3°C | 75 mm | 5.8 | 12 h 25 | 81 | Good coverage |
| October | 18.9°C | 4.6°C | 65 mm | 5.1 | 11 h 03 | 58 | Good coverage |
| November | 9.5°C | -2.7°C | 39 mm | 4.2 | 9 h 51 | 19 | Good coverage |
| December | 3.6°C | -7.3°C | 19 mm | 2.9 | 9 h 16 | 5 | Good coverage |
| Month | Record high | Record low | Wettest day | Wettest / driest month | Years |
|---|---|---|---|---|---|
| January | 21.7°C16 Jan 2006 | -35.0°C12 Jan 1912 | 25 mm23 Jan 1965 | 55 mm1915 · driest 0 mm in 1981 | 63 |
| February | 26.1°C26 Feb 1995 | -33.3°C4 Feb 1917 | 45 mm19 Feb 1971 | 73 mm1971 · driest 0 mm in 2003 | 63 |
| March | 32.8°C23 Mar 1910 | -23.9°C4 Mar 1978 | 74 mm29 Mar 1981 | 233 mm1987 · driest 1 mm in 1994 | 63 |
| April | 37.8°C29 Apr 1910 | -12.2°C3 Apr 1975 | 75 mm13 Apr 1977 | 188 mm1984 · driest 4 mm in 1907 | 63 |
| May | 37.8°C24 May 1967 | -5.6°C2 May 1909 | 86 mm12 May 2005 | 306 mm1903 · driest 18 mm in 1901 | 62 |
| June | 41.7°C22 Jun 1988 | 3.9°C4 Jun 1998 | 163 mm4 Jun 1980 | 272 mm1980 · driest 14 mm in 1911 | 62 |
| July | 46.7°C24 Jul 1936 | 5.6°C27 Jul 1906 | 111 mm24 Jul 1968 | 206 mm1993 · driest 15 mm in 1974 | 63 |
| August | 43.3°C23 Aug 1943 | 5.0°C22 Aug 1904 | 89 mm17 Aug 1910 | 194 mm1977 · driest 10 mm in 1976 | 63 |
| September | 41.1°C6 Sep 1913 | -4.4°C29 Sep 1984 | 102 mm9 Sep 1914 | 204 mm1989 · driest 6 mm in 1980 | 64 |
| October | 35.6°C4 Oct 1938 | -20.6°C27 Oct 1913 | 67 mm16 Oct 1968 | 219 mm2007 · driest 0 mm in 1988 | 66 |
| November | 28.9°C9 Nov 2006 | -22.8°C28 Nov 1976 | 61 mm20 Nov 1975 | 105 mm1983 · driest 0 mm in 1906 | 62 |
| December | 25.6°C23 Dec 1964 | -33.3°C23 Dec 1989 | 31 mm29 Dec 1906 | 69 mm1973 · driest 0 mm in 1903 | 61 |
| Month | Days 25°C+ | Days 30°C+ | Frost nights | Heavy rain (10 mm+) | Snow days |
|---|---|---|---|---|---|
| January | 0 | 0 | 30 | <1 | 4 |
| February | <1 | 0 | 25 | <1 | 3 |
| March | <1 | 0 | 21 | 1 | 2 |
| April | 4 | 1 | 7 | 2 | <1 |
| May | 11 | 3 | <1 | 5 | 0 |
| June | 22 | 11 | 0 | 4 | 0 |
| July | 28 | 17 | 0 | 3 | 0 |
| August | 26 | 14 | 0 | 3 | 0 |
| September | 17 | 7 | <1 | 2 | <1 |
| October | 6 | 2 | 6 | 2 | <1 |
| November | <1 | 0 | 21 | 1 | 2 |
| December | 0 | 0 | 29 | <1 | 3 |
| Month | Warm & dry days | Wet days | Washouts | Week with 3+ wet days | Daytime mean has ranged |
|---|---|---|---|---|---|
| January | <1% | 9% | 1% | 4% | -2.7–6.3°C |
| February | 2% | 12% | 2% | 7% | -0.8–8.7°C |
| March | 12% | 16% | 4% | 11% | 4.6–15.0°C |
| April | 34% | 23% | 8% | 24% | 13.8–20.6°C |
| May | 55% | 29% | 12% | 33% | 20.8–25.9°C |
| June | 72% | 28% | 11% | 30% | 26.0–31.0°C |
| July | 76% | 23% | 8% | 21% | 28.8–34.8°C |
| August | 78% | 22% | 9% | 19% | 27.6–32.6°C |
| September | 71% | 19% | 8% | 15% | 23.2–27.8°C |
| October | 47% | 14% | 5% | 12% | 16.9–22.0°C |
| November | 10% | 11% | 3% | 7% | 6.6–13.2°C |
| December | <1% | 9% | 2% | 4% | -1.2–7.0°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