Dover weather in September: Dover, Delaware: normal highs, lows, rain and records for September
Dover in September has a normal high of 79°F and a normal low of 61°F, a daily mean of 70°F, falling from 83°F on the 1st to 75°F by the 30th. Measurable precipitation falls on 8 days in a normal September, 4.25 inches in all. (NOAA 1991-2020 normals)
In metric: a normal high of 26°C and low of 16°C, 108 mm of precipitation in September.
- NOAA stationDover
- Station IDUSC00072730
- Location39.15°N 75.51°W
- Elevation30 ft (9 m)
- Population40,191
- Jan 44° 28°
- Feb 47° 29°
- Mar 55° 35°
- Apr 66° 45°
- May 74° 54°
- Jun 83° 64°
- Jul 87° 69°
- Aug 85° 67°
- Sep 79° 61°
- Oct 69° 50°
- Nov 58° 39°
- Dec 49° 32°
Each month: normal high (large) and low, °F. Fill: the month's normal mean, colder blue to hotter red.
How warm is Dover in September?
The normal high is 79°F and the normal low 61°F, for a daily mean of 70.1°F. September is 6.1°F cooler than August and 10.9°F warmer than October. September is the 4th warmest month of the year in Dover and the 3rd wettest. Across the month the normal high falls 8°F, from 83°F on September 1 to 75°F on September 30. From one year to the next September's mean temperature typically moves about 2.1°F either way (NOAA's standard deviation), so roughly two Septembers in three average between 68°F and 72°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 28%).
| Day | High | Low | Chance of 0.01 in | Chance of 0.10 in |
|---|---|---|---|---|
| September 1 | 83°F | 65°F | 25% | 17% |
| September 8 | 82°F | 64°F | 26% | 17% |
| September 15 | 80°F | 62°F | 26% | 17% |
| September 22 | 77°F | 59°F | 27% | 18% |
| September 30 | 75°F | 56°F | 28% | 18% |
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 | 83°F | 65°F | 25% | 17% | 13 h 10 min |
| September 2 | 83°F | 65°F | 25% | 17% | 13 h |
| September 3 | 83°F | 65°F | 25% | 17% | 13 h |
| September 4 | 83°F | 65°F | 25% | 17% | 13 h |
| September 5 | 82°F | 64°F | 26% | 17% | 13 h |
| September 6 | 82°F | 64°F | 26% | 17% | 12 h 50 min |
| September 7 | 82°F | 64°F | 26% | 17% | 12 h 50 min |
| September 8 | 82°F | 64°F | 26% | 17% | 12 h 50 min |
| September 9 | 81°F | 63°F | 26% | 17% | 12 h 50 min |
| September 10 | 81°F | 63°F | 26% | 17% | 12 h 40 min |
| September 11 | 81°F | 63°F | 26% | 17% | 12 h 40 min |
| September 12 | 81°F | 62°F | 26% | 17% | 12 h 40 min |
| September 13 | 80°F | 62°F | 26% | 17% | 12 h 40 min |
| September 14 | 80°F | 62°F | 26% | 17% | 12 h 30 min |
| September 15 | 80°F | 62°F | 26% | 17% | 12 h 30 min |
| September 16 | 79°F | 61°F | 26% | 17% | 12 h 30 min |
| September 17 | 79°F | 61°F | 27% | 17% | 12 h 30 min |
| September 18 | 79°F | 60°F | 27% | 17% | 12 h 20 min |
| September 19 | 78°F | 60°F | 27% | 17% | 12 h 20 min |
| September 20 | 78°F | 60°F | 27% | 18% | 12 h 20 min |
| September 21 | 78°F | 59°F | 27% | 18% | 12 h 20 min |
| September 22 | 77°F | 59°F | 27% | 18% | 12 h 10 min |
| September 23 | 77°F | 59°F | 28% | 18% | 12 h 10 min |
| September 24 | 77°F | 58°F | 28% | 18% | 12 h 10 min |
| September 25 | 76°F | 58°F | 28% | 18% | 12 h 10 min |
| September 26 | 76°F | 58°F | 28% | 18% | 12 h |
| September 27 | 76°F | 57°F | 28% | 18% | 12 h |
| September 28 | 75°F | 57°F | 28% | 18% | 12 h |
| September 29 | 75°F | 56°F | 28% | 18% | 11 h 50 min |
| September 30 | 75°F | 56°F | 28% | 18% | 11 h 50 min |
- Normal high
- 79°FSeptember average
- Normal low
- 61°FSeptember average
- Precipitation
- 4.25 inmonth total
- Days with precipitation
- 80.01 inch or more
- Days at 90°F or more
- 2
- Daylight
- 13 h 10 min to 11 h 50 minSeptember 1 to September 30
- Days at 70°F or more
- 28
- Days at 80°F or more
- 16
- Sunshine
- 77%of clear-sky sunlight (NASA)
Source: NOAA NCEI 1991-2020 daily normals, station USC00072730; monthly normals. Daylight is computed from the place's latitude with NOAA's solar equations.
Does it rain in Dover in September?
On a given September day the chance of 0.01 inch or more is 27% on average, highest around September 27 (28%). In all, 4.25 in falls on 8 days of a normal September, 1 of them with an inch or more.
In a normal September in Dover, 2 days reach 90°F.
Source: NOAA NCEI 1991-2020 daily and monthly normals, station USC00072730.
What are the records for September in Dover?
The warmest September temperature on this station's record (since 1893) is 99°F, on September 1, 1953; the coldest is 30°F, on September 8, 1924. The wettest September brought 10.52 in (1971).
The September mean against the 1991-2020 normal of 70.1°F: 2022 71.0°F (+0.9), 2023 71.3°F (+1.2), 2024 70.9°F (+0.8), 2025 70.9°F (+0.8), 2026 72.0°F (+1.9). 5 of 5 ran warmer than normal.
| September | Mean | Against normal | Precip. |
|---|---|---|---|
| 2022 | 71.0°F | +0.9°F | 3.08 in |
| 2023 | 71.3°F | +1.2°F | 5.70 in |
| 2024 | 70.9°F | +0.8°F | 1.13 in |
| 2025 | 70.9°F | +0.8°F | 4.65 in |
| 2026 | 72.0°F | +1.9°F | – |
Source: records: ACIS, station USC00072730; recent months: ACIS, station USC00072730. Records and recent months use complete months only.
How does September in Dover compare across Delaware?
Across the 6 places PlainClimate covers in Delaware, September normal highs run from 79°F in Wilmington to 80°F in Lewes; Dover's is 79°F.
Source: NOAA NCEI 1991-2020 monthly normals for every station in the state.