September
September · May · June
United States · 1991–2020
September leads for comfortable weather in Pottsgrove: typically 24.9°C by day, 13.4°C at night, with 121 mm of rain. Based on measured 1991–2020 NOAA station history.
September · May · June
July · August · June
May · October · April
The weakest month is January, scoring 5 against September’s 78 — days reach only 3.6°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 | 3.6°C | -5.3°C | 70 mm | 7.7 | 9 h 36 | 5 | Good coverage |
| February | 5.3°C | -4.5°C | 66 mm | 7.7 | 10 h 36 | 5 | Good coverage |
| March | 10.5°C | -0.4°C | 93 mm | 8.4 | 11 h 49 | 15 | Good coverage |
| April | 17.2°C | 5°C | 97 mm | 8.8 | 13 h 13 | 46 | Good coverage |
| May | 22.5°C | 10.6°C | 97 mm | 9.5 | 14 h 23 | 73 | Good coverage |
| June | 27°C | 15.7°C | 107 mm | 9.2 | 15 h 01 | 73 | Good coverage |
| July | 29.8°C | 18.4°C | 119 mm | 8.7 | 14 h 46 | 58 | Good coverage |
| August | 28.5°C | 17.5°C | 124 mm | 8.5 | 13 h 46 | 63 | Good coverage |
| September | 24.9°C | 13.4°C | 121 mm | 7.6 | 12 h 24 | 78 | Good coverage |
| October | 18.3°C | 7.1°C | 104 mm | 8 | 11 h 04 | 53 | Good coverage |
| November | 12.4°C | 1.6°C | 76 mm | 7 | 9 h 53 | 28 | Good coverage |
| December | 6.4°C | -2.6°C | 98 mm | 8.5 | 9 h 19 | 5 | Good coverage |
| Month | Record high | Record low | Wettest day | Wettest / driest month | Years |
|---|---|---|---|---|---|
| January | 21.7°C6 Jan 2007 | -21.6°C31 Jan 2019 | 57 mm9 Jan 2024 | 148 mm2024 · driest 13 mm in 2025 | 27 |
| February | 25.6°C21 Feb 2018 | -18.8°C1 Feb 2019 | 65 mm13 Feb 2008 | 151 mm2008 · driest 13 mm in 2002 | 27 |
| March | 28.9°C29 Mar 2025 | -17.7°C6 Mar 2015 | 69 mm21 Mar 2000 | 170 mm2000 · driest 24 mm in 2006 | 28 |
| April | 33.3°C27 Apr 2009 | -6.0°C6 Apr 2016 | 123 mm30 Apr 2014 | 232 mm2014 · driest 35 mm in 2021 | 28 |
| May | 34.4°C31 May 2011 | -1.1°C4 May 2002 | 56 mm13 May 2006 | 187 mm2025 · driest 3 mm in 2023 | 28 |
| June | 36.7°C22 Jun 2024 | 4.4°C1 Jun 2020 | 99 mm20 Jun 2003 | 294 mm2003 · driest 18 mm in 1999 | 28 |
| July | 40.6°C22 Jul 2011 | 8.9°C3 Jul 2001 | 109 mm12 Jul 2004 | 310 mm2004 · driest 0 mm in 1999 | 28 |
| August | 38.3°C9 Aug 2001 | 7.2°C31 Aug 2025 | 129 mm4 Aug 2020 | 274 mm2011 · driest 10 mm in 2025 | 27 |
| September | 36.7°C1 Sep 2010 | 1.1°C21 Sep 2020 | 137 mm1 Sep 2021 | 288 mm2011 · driest 13 mm in 2007 | 27 |
| October | 32.8°C2 Oct 2019 | -3.8°C19 Oct 2015 | 121 mm8 Oct 2005 | 242 mm2005 · driest 1 mm in 2024 | 27 |
| November | 28.3°C6 Nov 2024 | -11.6°C23 Nov 2018 | 57 mm30 Nov 2020 | 200 mm2018 · driest 15 mm in 2025 | 27 |
| December | 22.8°C1 Dec 2006 | -17.8°C14 Dec 2005 | 58 mm27 Dec 2023 | 201 mm2023 · driest 21 mm in 2025 | 27 |
| Month | Days 25°C+ | Days 30°C+ | Frost nights | Heavy rain (10 mm+) |
|---|---|---|---|---|
| January | 0 | 0 | 26 | 3 |
| February | 0 | 0 | 24 | 2 |
| March | <1 | 0 | 18 | 4 |
| April | 3 | <1 | 4 | 3 |
| May | 11 | 3 | <1 | 3 |
| June | 22 | 8 | 0 | 3 |
| July | 29 | 16 | 0 | 4 |
| August | 27 | 11 | 0 | 4 |
| September | 16 | 3 | 0 | 4 |
| October | 3 | <1 | 2 | 4 |
| November | <1 | 0 | 13 | 3 |
| December | 0 | 0 | 23 | 4 |
| Month | Warm & dry days | Wet days | Washouts | Week with 3+ wet days | Daytime mean has ranged |
|---|---|---|---|---|---|
| January | <1% | 25% | 8% | 23% | 1.0–6.9°C |
| February | <1% | 27% | 7% | 30% | 1.5–8.4°C |
| March | 7% | 27% | 11% | 31% | 7.5–14.4°C |
| April | 26% | 29% | 9% | 35% | 15.0–19.2°C |
| May | 52% | 31% | 11% | 39% | 20.3–24.8°C |
| June | 69% | 30% | 11% | 34% | 25.4–29.2°C |
| July | 72% | 28% | 11% | 34% | 27.8–31.8°C |
| August | 73% | 27% | 11% | 30% | 26.7–30.0°C |
| September | 69% | 26% | 11% | 29% | 23.5–27.0°C |
| October | 32% | 25% | 12% | 26% | 16.7–20.1°C |
| November | 7% | 22% | 8% | 21% | 9.9–14.9°C |
| December | <1% | 27% | 11% | 31% | 3.8–9.6°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