September
September · May · August
United States · 1991–2020
September leads for comfortable weather in Tiffin: typically 25.1°C by day, 11.9°C at night, with 78 mm of rain. Based on measured 1991–2020 NOAA station history.
September · May · August
July · August · June
October · May · September
The weakest month is January, scoring 5 against September’s 82 — days reach only -0.8°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 | -0.8°C | -10.1°C | 22 mm | 4.3 | 9 h 28 | 5 | Strong coverage |
| February | 1.6°C | -8.2°C | 33 mm | 5.1 | 10 h 32 | 5 | Strong coverage |
| March | 9.2°C | -2°C | 54 mm | 6.8 | 11 h 48 | 14 | Strong coverage |
| April | 16.7°C | 4°C | 91 mm | 8.9 | 13 h 16 | 43 | Strong coverage |
| May | 22.5°C | 10.5°C | 116 mm | 9.6 | 14 h 31 | 70 | Strong coverage |
| June | 27.6°C | 16.2°C | 126 mm | 9.6 | 15 h 11 | 67 | Strong coverage |
| July | 29.5°C | 18.3°C | 88 mm | 6.7 | 14 h 55 | 65 | Strong coverage |
| August | 28.5°C | 17°C | 94 mm | 7.1 | 13 h 51 | 70 | Strong coverage |
| September | 25.1°C | 11.9°C | 78 mm | 6.5 | 12 h 25 | 82 | Strong coverage |
| October | 17.4°C | 5°C | 77 mm | 6.8 | 11 h 01 | 51 | Strong coverage |
| November | 9.4°C | -1.4°C | 44 mm | 5.4 | 9 h 46 | 19 | Strong coverage |
| December | 1.8°C | -7.3°C | 36 mm | 5.1 | 9 h 10 | 5 | Strong coverage |
| Month | Record high | Record low | Wettest day | Wettest / driest month | Years |
|---|---|---|---|---|---|
| January | 18.3°C8 Jan 2003 | -33.3°C31 Jan 1996 | 36 mm25 Jan 1950 | 84 mm1950 · driest 1 mm in 1948 | 37 |
| February | 25.0°C27 Feb 2024 | -36.7°C3 Feb 1996 | 42 mm27 Feb 1948 | 103 mm2001 · driest 4 mm in 2026 | 37 |
| March | 32.8°C21 Mar 2026 | -26.7°C12 Mar 1948 | 43 mm8 Mar 2009 | 141 mm1951 · driest 10 mm in 2003 | 37 |
| April | 33.3°C29 Apr 1952 | -9.3°C2 Apr 2018 | 101 mm17 Apr 2013 | 215 mm2013 · driest 17 mm in 2018 | 37 |
| May | 36.7°C28 May 2018 | -4.4°C3 May 2005 | 119 mm9 May 1996 | 300 mm1996 · driest 41 mm in 2006 | 37 |
| June | 37.2°C27 Jun 2012 | 5.0°C4 Jun 1950 | 144 mm22 Jun 2007 | 249 mm2014 · driest 24 mm in 1997 | 36 |
| July | 40.6°C25 Jul 2012 | 7.8°C5 Jul 1997 | 77 mm3 Jul 2004 | 201 mm1948 · driest 7 mm in 2012 | 36 |
| August | 38.3°C30 Aug 2013 | 4.4°C20 Aug 1950 | 85 mm23 Aug 2002 | 212 mm2018 · driest 2 mm in 2013 | 36 |
| September | 38.3°C9 Sep 2013 | -3.3°C23 Sep 1995 | 70 mm5 Sep 2018 | 190 mm2019 · driest 1 mm in 2024 | 36 |
| October | 33.9°C3 Oct 2006 | -11.7°C29 Oct 1952 | 90 mm17 Oct 1998 | 184 mm2009 · driest 0 mm in 1952 | 36 |
| November | 26.1°C1 Nov 2000 | -19.4°C24 Nov 1950 | 67 mm16 Nov 1952 | 147 mm1952 · driest 1 mm in 1997 | 36 |
| December | 23.9°C15 Dec 2021 | -28.3°C15 Dec 1951 | 40 mm13 Dec 2015 | 88 mm2015 · driest 4 mm in 1995 | 36 |
| 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 | 21 | 2 |
| April | 4 | <1 | 7 | 3 |
| May | 12 | 2 | <1 | 4 |
| June | 23 | 10 | 0 | 4 |
| July | 29 | 15 | 0 | 3 |
| August | 27 | 11 | 0 | 3 |
| September | 17 | 6 | <1 | 3 |
| October | 4 | <1 | 6 | 2 |
| November | <1 | 0 | 19 | 1 |
| December | 0 | 0 | 28 | 1 |
| Month | Warm & dry days | Wet days | Washouts | Week with 3+ wet days | Daytime mean has ranged |
|---|---|---|---|---|---|
| January | 0% | 15% | 2% | 8% | -3.6–1.4°C |
| February | <1% | 18% | 4% | 14% | -3.4–5.9°C |
| March | 8% | 24% | 7% | 23% | 5.3–13.1°C |
| April | 25% | 29% | 10% | 35% | 13.5–19.5°C |
| May | 52% | 30% | 11% | 37% | 20.6–25.1°C |
| June | 67% | 31% | 12% | 37% | 26.2–29.8°C |
| July | 76% | 23% | 11% | 22% | 27.8–31.6°C |
| August | 78% | 22% | 9% | 19% | 27.0–30.2°C |
| September | 72% | 19% | 8% | 19% | 22.7–27.5°C |
| October | 34% | 20% | 7% | 20% | 15.0–20.4°C |
| November | 6% | 17% | 5% | 13% | 5.2–12.3°C |
| December | <1% | 18% | 4% | 12% | -1.7–5.7°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