Plymouth weather in September: Plymouth, Massachusetts: normal highs, lows, rain and records for September
Plymouth in September has a normal high of 73°F and a normal low of 53°F, a daily mean of 63°F, falling from 78°F on the 1st to 68°F by the 30th. Measurable precipitation falls on 13 days in a normal September, 3.82 inches in all. (NOAA 1991-2020 normals)
In metric: a normal high of 23°C and low of 12°C, 97 mm of precipitation in September.
- NOAA stationPlymouth Municipal Airport
- Station IDUSW00054769
- Location41.91°N 70.73°W
- Elevation149 ft (45 m)
- Population (town)66,663
- Census place7,852
- Jan 38° 20°
- Feb 40° 21°
- Mar 46° 27°
- Apr 57° 36°
- May 67° 46°
- Jun 76° 55°
- Jul 82° 62°
- Aug 80° 61°
- Sep 73° 53°
- Oct 63° 42°
- Nov 53° 33°
- Dec 43° 26°
Each month: normal high (large) and low, °F. Fill: the month's normal mean, colder blue to hotter red.
How warm is Plymouth in September?
The normal high is 73°F and the normal low 53°F, for a daily mean of 63.2°F. September is 7.3°F cooler than August and 10.8°F warmer than October. September is the 4th warmest month of the year in Plymouth and the 7th wettest. Across the month the normal high falls 10°F, from 78°F on September 1 to 68°F on September 30. From one year to the next September's mean temperature typically moves about 1.8°F either way (NOAA's standard deviation), so roughly two Septembers in three average between 61°F and 65°F.
Bars above: each day's normal high to low. Columns below: the chance of 0.01 inch or more of precipitation that day, on a scale of 0 to 100% (highest 46%).
| Day | High | Low | Chance of 0.01 in | Chance of 0.10 in |
|---|---|---|---|---|
| September 1 | 78°F | 58°F | 43% | 19% |
| September 8 | 76°F | 56°F | 43% | 19% |
| September 15 | 74°F | 53°F | 44% | 20% |
| September 22 | 71°F | 51°F | 45% | 21% |
| September 30 | 68°F | 48°F | 46% | 22% |
Every day of September: normal high, low and chance of precipitation (warmest afternoon September 1, coldest night September 30)
| Day | High | Low | Chance of 0.01 in | Chance of 0.10 in | Daylight |
|---|---|---|---|---|---|
| September 1 | 78°F | 58°F | 43% | 19% | 13 h 10 min |
| September 2 | 78°F | 58°F | 43% | 19% | 13 h 10 min |
| September 3 | 77°F | 57°F | 43% | 19% | 13 h 10 min |
| September 4 | 77°F | 57°F | 43% | 19% | 13 h |
| September 5 | 77°F | 57°F | 43% | 19% | 13 h |
| September 6 | 76°F | 56°F | 43% | 19% | 13 h |
| September 7 | 76°F | 56°F | 43% | 19% | 13 h |
| September 8 | 76°F | 56°F | 43% | 19% | 12 h 50 min |
| September 9 | 76°F | 55°F | 43% | 19% | 12 h 50 min |
| September 10 | 75°F | 55°F | 43% | 19% | 12 h 50 min |
| September 11 | 75°F | 55°F | 44% | 19% | 12 h 40 min |
| September 12 | 75°F | 54°F | 44% | 19% | 12 h 40 min |
| September 13 | 74°F | 54°F | 44% | 19% | 12 h 40 min |
| September 14 | 74°F | 54°F | 44% | 19% | 12 h 40 min |
| September 15 | 74°F | 53°F | 44% | 20% | 12 h 30 min |
| September 16 | 73°F | 53°F | 44% | 20% | 12 h 30 min |
| September 17 | 73°F | 53°F | 45% | 20% | 12 h 30 min |
| September 18 | 73°F | 52°F | 45% | 20% | 12 h 20 min |
| September 19 | 72°F | 52°F | 45% | 20% | 12 h 20 min |
| September 20 | 72°F | 52°F | 45% | 20% | 12 h 20 min |
| September 21 | 71°F | 51°F | 45% | 20% | 12 h 20 min |
| September 22 | 71°F | 51°F | 45% | 21% | 12 h 10 min |
| September 23 | 71°F | 51°F | 45% | 21% | 12 h 10 min |
| September 24 | 70°F | 50°F | 46% | 21% | 12 h 10 min |
| September 25 | 70°F | 50°F | 46% | 21% | 12 h 10 min |
| September 26 | 70°F | 49°F | 46% | 21% | 12 h |
| September 27 | 69°F | 49°F | 46% | 21% | 12 h |
| September 28 | 69°F | 49°F | 46% | 22% | 12 h |
| September 29 | 68°F | 48°F | 46% | 22% | 11 h 50 min |
| September 30 | 68°F | 48°F | 46% | 22% | 11 h 50 min |
- Normal high
- 73°FSeptember average
- Normal low
- 53°FSeptember average
- Precipitation
- 3.82 inmonth total
- Days with precipitation
- 130.01 inch or more
- Daylight
- 13 h 10 min to 11 h 50 minSeptember 1 to September 30
- Days at 70°F or more
- 21
- Days at 80°F or more
- 7
- Sunshine
- 79%of clear-sky sunlight (NASA)
Source: NOAA NCEI 1991-2020 daily normals, station USW00054769; monthly normals. Daylight is computed from the place's latitude with NOAA's solar equations.
Does it rain in Plymouth in September?
On a given September day the chance of 0.01 inch or more is 44% on average, highest around September 29 (46%). In all, 3.82 in falls on 13 days of a normal September, 1 of them with an inch or more.
Source: NOAA NCEI 1991-2020 daily and monthly normals, station USW00054769.
How humid and windy is Plymouth in September?
At 3 p.m. the normal temperature is 66°F with 61% relative humidity and a dew point of 52°F; at 6 a.m. it is 53°F with 90% humidity. The wind averages 6.7 mph, most often from the west in the afternoon.
| Time | Temperature | Dew point | Humidity | Wind | Clear or few clouds |
|---|---|---|---|---|---|
| 6 a.m. | 53°F | 51°F | 90% | 4.9 mph | – |
| 9 a.m. | 62°F | 53°F | 72% | 8.8 mph | – |
| noon | 66°F | 52°F | 61% | 10.0 mph | – |
| 3 p.m. | 66°F | 52°F | 61% | 9.6 mph | – |
| 6 p.m. | 60°F | 53°F | 78% | 5.7 mph | – |
| 9 p.m. | 56°F | 52°F | 86% | 5.0 mph | – |
Source: NOAA NCEI 1991-2020 hourly normals, station USW00054769. Hourly normals exist only for NOAA's first-order stations; a dash where NOAA publishes no value for that hour (the sky at some hours).
What are the records for September in Plymouth?
The warmest September temperature on this station's record (since 1996) is 96°F, on September 2, 2010; the coldest is 32°F, on September 30, 2000. The wettest September brought 11.48 in (2021).
The September mean against the 1991-2020 normal of 63.2°F: 2021 66.2°F (+3.0), 2022 64.0°F (+0.8), 2023 66.8°F (+3.6), 2024 64.3°F (+1.1), 2025 64.1°F (+0.9), 2026 63.4°F (+0.2). 6 of 6 ran warmer than normal.
| September | Mean | Against normal | Precip. |
|---|---|---|---|
| 2021 | 66.2°F | +3.0°F | 11.48 in |
| 2022 | 64.0°F | +0.8°F | 3.33 in |
| 2023 | 66.8°F | +3.6°F | 7.05 in |
| 2024 | 64.3°F | +1.1°F | 5.86 in |
| 2025 | 64.1°F | +0.9°F | – |
| 2026 | 63.4°F | +0.2°F | 9.39 in |
Source: records: ACIS, station USW00054769; recent months: ACIS, station USW00054769. Records and recent months use complete months only.
How does September in Plymouth compare across Massachusetts?
Across the 35 places PlainClimate covers in Massachusetts, September normal highs run from 70°F in East Sandwich to 78°F in Maynard; Plymouth's is 73°F.
Source: NOAA NCEI 1991-2020 monthly normals for every station in the state.
Other months and places
- Plymouth in August80°F by day, 61°F at night
- Plymouth in October63°F by day, 42°F at night
- Plymouth through the yearEvery month, frost dates, records and recent years
- Massachusetts in SeptemberThe statewide normal and the warmest and coolest places
- Maynard: Massachusetts's warmest Septembernormal high 78°F