September
September · August · June
United States · 1991–2020
September leads for comfortable weather in Yorkville: typically 24.6°C by day, 10.8°C at night, with 74 mm of rain. Based on measured 1991–2020 NOAA station history.
September · August · June
July · August · June
September · May · October
The weakest month is January, scoring 5 against September’s 82 — days reach only -0.9°C, 25° below the 24°C the score treats as ideal.
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 | -0.9°C | -10°C | 33 mm | 5.1 | 9 h 28 | 5 | Good coverage |
| February | 1.2°C | -8.7°C | 36 mm | 4.9 | 10 h 32 | 5 | Good coverage |
| March | 8.5°C | -2.5°C | 53 mm | 7.4 | 11 h 48 | 11 | Good coverage |
| April | 15.9°C | 2.9°C | 93 mm | 9.2 | 13 h 16 | 38 | Good coverage |
| May | 22°C | 9.2°C | 116 mm | 11 | 14 h 30 | 64 | Good coverage |
| June | 27.1°C | 14.6°C | 102 mm | 9.6 | 15 h 11 | 74 | Good coverage |
| July | 29°C | 16.4°C | 84 mm | 7.7 | 14 h 55 | 70 | Good coverage |
| August | 27.7°C | 15°C | 88 mm | 7.2 | 13 h 51 | 76 | Good coverage |
| September | 24.6°C | 10.8°C | 74 mm | 6.4 | 12 h 25 | 82 | Good coverage |
| October | 17.1°C | 4.3°C | 79 mm | 7.7 | 11 h 01 | 48 | Good coverage |
| November | 9.4°C | -1.3°C | 55 mm | 6.3 | 9 h 47 | 17 | Good coverage |
| December | 2°C | -6.9°C | 46 mm | 5.9 | 9 h 10 | 5 | Good coverage |
| Month | Record high | Record low | Wettest day | Wettest / driest month | Years |
|---|---|---|---|---|---|
| January | 17.8°C7 Jan 2008 | -36.0°C16 Jan 2009 | 28 mm29 Jan 2013 | 84 mm2013 · driest 4 mm in 2004 | 28 |
| February | 23.3°C27 Feb 2024 | -30.5°C11 Feb 2014 | 49 mm26 Feb 2009 | 90 mm2023 · driest 1 mm in 2003 | 28 |
| March | 28.3°C20 Mar 2012 | -24.4°C4 Mar 2002 | 41 mm30 Mar 2017 | 128 mm2026 · driest 11 mm in 2015 | 28 |
| April | 32.2°C18 Apr 2002 | -9.9°C7 Apr 2018 | 64 mm22 Apr 1999 | 191 mm2013 · driest 27 mm in 2021 | 28 |
| May | 36.1°C27 May 2012 | -6.1°C3 May 2005 | 60 mm30 May 2004 | 250 mm2019 · driest 32 mm in 2023 | 28 |
| June | 36.7°C28 Jun 2012 | 1.7°C1 Jun 2003 | 73 mm15 Jun 2015 | 228 mm2014 · driest 13 mm in 2005 | 28 |
| July | 38.9°C7 Jul 2012 | 6.7°C2 Jul 2001 | 110 mm2 Jul 2026 | 244 mm2026 · driest 0 mm in 2002 | 28 |
| August | 36.1°C2 Aug 2006 | 4.4°C31 Aug 2009 | 94 mm8 Aug 2007 | 218 mm2007 · driest 12 mm in 2020 | 27 |
| September | 35.0°C13 Sep 2005 | -1.6°C24 Sep 2012 | 131 mm13 Sep 2008 | 249 mm2008 · driest 12 mm in 2009 | 27 |
| October | 32.8°C3 Oct 2025 | -7.2°C2 Oct 2003 | 131 mm14 Oct 2017 | 250 mm2017 · driest 11 mm in 2005 | 28 |
| November | 25.0°C1 Nov 2016 | -17.7°C22 Nov 2015 | 45 mm4 Nov 2003 | 144 mm2003 · driest 12 mm in 2021 | 28 |
| December | 21.1°C3 Dec 2012 | -27.7°C19 Dec 2016 | 44 mm27 Dec 2008 | 141 mm2015 · driest 11 mm in 2017 | 28 |
| Month | Days 25°C+ | Days 30°C+ | Frost nights | Heavy rain (10 mm+) |
|---|---|---|---|---|
| January | 0 | 0 | 29 | 1 |
| February | 0 | 0 | 26 | 1 |
| March | <1 | 0 | 23 | 2 |
| April | 3 | <1 | 10 | 3 |
| May | 10 | 3 | 1 | 4 |
| June | 22 | 8 | 0 | 3 |
| July | 28 | 13 | 0 | 3 |
| August | 25 | 8 | 0 | 3 |
| September | 16 | 4 | <1 | 2 |
| October | 4 | <1 | 8 | 3 |
| November | 0 | 0 | 19 | 2 |
| December | 0 | 0 | 26 | 2 |
| Month | Warm & dry days | Wet days | Washouts | Week with 3+ wet days | Daytime mean has ranged |
|---|---|---|---|---|---|
| January | 0% | 17% | 4% | 14% | -3.4–2.3°C |
| February | <1% | 16% | 4% | 14% | -5.0–5.6°C |
| March | 5% | 25% | 6% | 32% | 6.2–12.9°C |
| April | 20% | 32% | 10% | 37% | 13.9–18.4°C |
| May | 46% | 33% | 11% | 40% | 20.0–24.7°C |
| June | 67% | 30% | 11% | 37% | 25.8–29.1°C |
| July | 74% | 26% | 11% | 30% | 26.9–30.8°C |
| August | 76% | 23% | 10% | 24% | 26.1–29.2°C |
| September | 69% | 20% | 7% | 21% | 23.0–26.9°C |
| October | 27% | 25% | 8% | 24% | 15.0–19.9°C |
| November | 5% | 20% | 6% | 21% | 6.0–12.7°C |
| December | <1% | 19% | 5% | 16% | -1.8–6.2°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