September
September · June · May
United States · 1991–2020
September leads for comfortable weather in Hillsborough: typically 25.2°C by day, 12.7°C at night, with 111 mm of rain. Based on measured 1991–2020 NOAA station history.
September · June · May
August · July · June
May · October · September
The weakest month is January, scoring 5 against September’s 77 — days reach only 3.8°C, 20° 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 | 3.8°C | -5.7°C | 99 mm | 9.6 | 9 h 34 | 5 | Good coverage |
| February | 5.3°C | -4.9°C | 78 mm | 8.4 | 10 h 36 | 5 | Good coverage |
| March | 9.7°C | -1.5°C | 108 mm | 9.4 | 11 h 49 | 7 | Good coverage |
| April | 16.7°C | 4°C | 108 mm | 10 | 13 h 13 | 40 | Good coverage |
| May | 22.2°C | 9.8°C | 117 mm | 11.5 | 14 h 24 | 66 | Good coverage |
| June | 26.9°C | 14.7°C | 118 mm | 10.3 | 15 h 03 | 72 | Good coverage |
| July | 29.7°C | 17.5°C | 147 mm | 10.1 | 14 h 48 | 55 | Good coverage |
| August | 28.6°C | 16.5°C | 125 mm | 9.2 | 13 h 46 | 64 | Good coverage |
| September | 25.2°C | 12.7°C | 111 mm | 7.8 | 12 h 25 | 77 | Good coverage |
| October | 18.3°C | 6.6°C | 118 mm | 9.3 | 11 h 03 | 49 | Good coverage |
| November | 11.9°C | 1.1°C | 82 mm | 7.5 | 9 h 52 | 25 | Good coverage |
| December | 6.4°C | -2.8°C | 117 mm | 10.1 | 9 h 18 | 5 | Good coverage |
| Month | Record high | Record low | Wettest day | Wettest / driest month | Years |
|---|---|---|---|---|---|
| January | 21.7°C7 Jan 2007 | -18.9°C29 Jan 2005 | 74 mm10 Jan 2024 | 211 mm1999 · driest 16 mm in 2025 | 26 |
| February | 25.0°C22 Feb 2018 | -19.4°C24 Feb 2015 | 61 mm13 Feb 2008 | 164 mm2018 · driest 17 mm in 2026 | 27 |
| March | 31.1°C31 Mar 1998 | -16.1°C6 Mar 2015 | 89 mm14 Mar 2010 | 252 mm2010 · driest 29 mm in 2006 | 28 |
| April | 32.8°C27 Apr 2009 | -5.0°C5 Apr 2016 | 123 mm16 Apr 2007 | 303 mm2007 · driest 41 mm in 2016 | 28 |
| May | 35.0°C21 May 1996 | -1.1°C15 May 1996 | 77 mm1 May 2014 | 221 mm1998 · driest 35 mm in 2015 | 28 |
| June | 36.1°C20 Jun 2025 | 3.3°C1 Jun 2001 | 72 mm8 Jun 2013 | 254 mm2006 · driest 17 mm in 1999 | 28 |
| July | 38.9°C7 Jul 1999 | 8.3°C20 Jul 1997 | 165 mm25 Jul 1997 | 263 mm2004 · driest 24 mm in 1999 | 28 |
| August | 38.3°C10 Aug 2001 | 6.7°C21 Aug 1998 | 177 mm28 Aug 2011 | 436 mm2011 · driest 33 mm in 2025 | 28 |
| September | 35.6°C2 Sep 2010 | 0.6°C30 Sep 2000 | 230 mm17 Sep 1999 | 378 mm1999 · driest 20 mm in 2019 | 27 |
| October | 33.3°C3 Oct 2019 | -3.3°C23 Oct 1997 | 105 mm9 Oct 2005 | 337 mm2005 · driest 0 mm in 2024 | 27 |
| November | 27.2°C1 Nov 2024 | -12.8°C24 Nov 2018 | 73 mm27 Nov 2013 | 228 mm2018 · driest 18 mm in 2021 | 27 |
| December | 24.4°C8 Dec 1998 | -16.7°C23 Dec 2024 | 83 mm18 Dec 2023 | 260 mm1996 · driest 26 mm in 1998 | 27 |
| Month | Days 25°C+ | Days 30°C+ | Frost nights | Heavy rain (10 mm+) | Snow days |
|---|---|---|---|---|---|
| January | 0 | 0 | 26 | 3 | 4 |
| February | 0 | 0 | 24 | 3 | 3 |
| March | <1 | 0 | 21 | 4 | 2 |
| April | 3 | <1 | 6 | 3 | <1 |
| May | 10 | 3 | <1 | 4 | 0 |
| June | 21 | 8 | 0 | 4 | 0 |
| July | 29 | 16 | 0 | 4 | 0 |
| August | 26 | 11 | 0 | 4 | 0 |
| September | 16 | 4 | 0 | 3 | 0 |
| October | 3 | <1 | 3 | 4 | <1 |
| November | 0 | 0 | 14 | 3 | <1 |
| December | 0 | 0 | 23 | 4 | 2 |
| Month | Warm & dry days | Wet days | Washouts | Week with 3+ wet days | Daytime mean has ranged |
|---|---|---|---|---|---|
| January | <1% | 27% | 10% | 31% | 0.5–7.0°C |
| February | <1% | 27% | 9% | 29% | 1.1–8.3°C |
| March | 6% | 27% | 10% | 32% | 6.9–12.9°C |
| April | 22% | 31% | 11% | 38% | 15.0–18.4°C |
| May | 49% | 33% | 12% | 45% | 20.2–24.0°C |
| June | 65% | 30% | 11% | 34% | 25.7–28.4°C |
| July | 67% | 30% | 13% | 35% | 27.8–31.2°C |
| August | 71% | 27% | 11% | 28% | 26.9–30.0°C |
| September | 69% | 25% | 10% | 26% | 23.7–26.9°C |
| October | 31% | 24% | 10% | 24% | 17.4–20.7°C |
| November | 6% | 26% | 10% | 27% | 9.4–14.3°C |
| December | <1% | 28% | 12% | 31% | 3.6–9.6°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