September
September · June · August
76climate match
United States · 1991–2020
Best time to visit
Sussex.
September leads for comfortable weather in Sussex: typically 24.1°C by day, 10.4°C at night, with 116 mm of rain. Based on measured 1991–2020 NOAA station history.
Best comfortSeptember
Typical high24.1°C
Typical low10.4°C
Rain in September116 mm
July
July · August · June
65climate match
May
May · September · October
70climate match
The weakest month is January, scoring 5 against September’s 76 — days reach only 2.1°C, 22° below the 24°C the score treats as ideal.
Month by month
The whole year,
without the guesswork.
The bars show the comfort score. Day and night temperatures come from daily observed highs and lows; rain is the historical monthly estimate.
Jan
52.1° / -8.8°
Feb
54° / -7.9°
Mar
58.9° / -3.7°
Apr
3416° / 2°
May
6421.8° / 7.6°
Jun
7226.1° / 12.7°
Jul
6628.9° / 15.7°
Aug
6928° / 14.7°
Sep
7624.1° / 10.4°
Oct
4317.7° / 4.3°
Nov
1911° / -0.9°
Dec
54.8° / -5.1°
| Month | Day | Night | Rain | Wet days | Daylight | Comfort | Coverage |
|---|---|---|---|---|---|---|---|
| January | 2.1°C | -8.8°C | 86 mm | 9 | 9 h 30 | 5 | Strong coverage |
| February | 4°C | -7.9°C | 68 mm | 7.6 | 10 h 33 | 5 | Strong coverage |
| March | 8.9°C | -3.7°C | 92 mm | 9.7 | 11 h 48 | 5 | Strong coverage |
| April | 16°C | 2°C | 103 mm | 10.2 | 13 h 15 | 34 | Strong coverage |
| May | 21.8°C | 7.6°C | 95 mm | 11.2 | 14 h 28 | 64 | Strong coverage |
| June | 26.1°C | 12.7°C | 111 mm | 9.7 | 15 h 08 | 72 | Strong coverage |
| July | 28.9°C | 15.7°C | 110 mm | 9.7 | 14 h 52 | 66 | Strong coverage |
| August | 28°C | 14.7°C | 115 mm | 9.1 | 13 h 49 | 69 | Strong coverage |
| September | 24.1°C | 10.4°C | 116 mm | 7.8 | 12 h 25 | 76 | Strong coverage |
| October | 17.7°C | 4.3°C | 122 mm | 8.8 | 11 h 02 | 43 | Strong coverage |
| November | 11°C | -0.9°C | 78 mm | 7.3 | 9 h 49 | 19 | Strong coverage |
| December | 4.8°C | -5.1°C | 100 mm | 9.4 | 9 h 13 | 5 | Strong coverage |
What has changed
Sussex runs +0.7°C
on the 1961–1990 baseline.
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.
Jan
+1.0
Feb
+1.2
Mar
+0.3
Apr
+0.9
May
+0.6
Jun
+0.2
Jul
+0.8
Aug
+0.4
Sep
+1.1
Oct
+0.5
Nov
+0.1
Dec
+1.8
| Month | Record high | Record low | Wettest day | Wettest / driest month | Years |
|---|---|---|---|---|---|
| January | 21.7°C6 Jan 2007 | -33.9°C21 Jan 1994 | 61 mm8 Jan 1996 | 258 mm1979 · driest 18 mm in 1955 | 127 |
| February | 25.0°C22 Feb 2018 | -30.6°C9 Feb 1967 | 74 mm3 Feb 1968 | 150 mm1902 · driest 18 mm in 1987 | 124 |
| March | 32.2°C28 Mar 1945 | -23.3°C19 Mar 1967 | 72 mm23 Mar 2010 | 225 mm2010 · driest 15 mm in 1915 | 128 |
| April | 35.0°C17 Apr 2002 | -12.8°C1 Apr 1923 | 107 mm18 Apr 1997 | 254 mm1983 · driest 20 mm in 1896 | 127 |
| May | 36.1°C9 May 1936 | -4.4°C3 May 1966 | 79 mm30 May 1984 | 269 mm1984 · driest 18 mm in 1903 | 127 |
| June | 36.7°C9 Jun 1933 | 0.6°C11 Jun 1980 | 102 mm12 Jun 1903 | 378 mm1903 · driest 5 mm in 1949 | 125 |
| July | 41.1°C10 Jul 1936 | 4.4°C3 Jul 1929 | 97 mm23 Jul 2019 | 324 mm1945 · driest 16 mm in 1894 | 126 |
| August | 38.9°C9 Aug 2001 | 1.1°C31 Aug 1965 | 164 mm28 Aug 2011 | 440 mm1955 · driest 15 mm in 1995 | 120 |
| September | 38.9°C3 Sep 1953 | -2.8°C27 Sep 1947 | 143 mm17 Sep 1999 | 368 mm2011 · driest 5 mm in 1938 | 126 |
| October | 33.3°C5 Oct 1941 | -10.6°C31 Oct 1925 | 181 mm8 Oct 2005 | 370 mm2005 · driest 0 mm in 1924 | 127 |
| November | 28.9°C1 Nov 1950 | -15.0°C23 Nov 2018 | 102 mm25 Nov 1950 | 259 mm1972 · driest 6 mm in 2023 | 123 |
| December | 23.9°C8 Dec 1998 | -25.0°C28 Dec 1950 | 78 mm17 Dec 2000 | 216 mm1972 · driest 18 mm in 1955 | 124 |
| Month | Days 25°C+ | Days 30°C+ | Frost nights | Heavy rain (10 mm+) | Snow days |
|---|---|---|---|---|---|
| January | 0 | 0 | 28 | 3 | 5 |
| February | 0 | 0 | 26 | 2 | 5 |
| March | <1 | 0 | 24 | 3 | 3 |
| April | 3 | <1 | 11 | 3 | <1 |
| May | 9 | 3 | 2 | 3 | 0 |
| June | 18 | 6 | 0 | 3 | 0 |
| July | 27 | 12 | 0 | 3 | 0 |
| August | 25 | 9 | 0 | 3 | 0 |
| September | 14 | 3 | <1 | 3 | 0 |
| October | 3 | 0 | 7 | 3 | <1 |
| November | <1 | 0 | 19 | 3 | <1 |
| December | 0 | 0 | 25 | 4 | 3 |
| Month | Warm & dry days | Wet days | Washouts | Week with 3+ wet days | Daytime mean has ranged |
|---|---|---|---|---|---|
| January | 0% | 28% | 10% | 30% | -1.3–5.2°C |
| February | <1% | 27% | 9% | 29% | -0.1–6.2°C |
| March | 4% | 29% | 10% | 37% | 5.4–11.7°C |
| April | 20% | 33% | 11% | 42% | 13.4–18.0°C |
| May | 50% | 33% | 11% | 42% | 19.5–24.7°C |
| June | 64% | 33% | 12% | 39% | 24.2–28.3°C |
| July | 69% | 31% | 12% | 36% | 27.1–30.5°C |
| August | 71% | 29% | 11% | 31% | 26.0–29.7°C |
| September | 63% | 26% | 11% | 26% | 22.2–26.2°C |
| October | 29% | 24% | 9% | 24% | 15.5–20.4°C |
| November | 4% | 27% | 10% | 29% | 8.2–13.3°C |
| December | <1% | 28% | 11% | 32% | 1.2–6.3°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
Nearby, measured,
and named.
- Place identity
- GeoNames 5105164
- NOAA station
- USC00288644 · SUSSEX 1 NW
- Station distance
- 1.5 km from the place centre
- Climate period
- 1991–2020
- Minimum month coverage
- 26 usable years
- Daylight
- Calculated from latitude 41.21°, mid-month, sunrise to sunset including refraction. Not a station measurement.
- Important limit
- Historical climate is not a forecast. Nearby stations can miss mountains, coasts, and local microclimates.