Sterling weather in September: Sterling, Virginia: normal highs, lows, rain and records for September
Sterling in September has a normal high of 79°F and a normal low of 58°F, a daily mean of 69°F, falling from 84°F on the 1st to 74°F by the 30th. Measurable precipitation falls on 9 days in a normal September, 3.94 inches in all. (NOAA 1991-2020 normals)
In metric: a normal high of 26°C and low of 14°C, 100 mm of precipitation in September.
- NOAA stationWashington Dulles International Airport
- Station IDUSW00093738
- Location38.94°N 77.46°W
- Elevation290 ft (88 m)
- From the center5 miles
- Population (census place)31,251
- Jan 43° 25°
- Feb 46° 27°
- Mar 55° 34°
- Apr 67° 43°
- May 75° 53°
- Jun 83° 62°
- Jul 88° 67°
- Aug 86° 65°
- Sep 79° 58°
- Oct 68° 45°
- Nov 57° 36°
- Dec 47° 29°
Each month: normal high (large) and low, °F. Fill: the month's normal mean, colder blue to hotter red.
How warm is Sterling in September?
The normal high is 79°F and the normal low 58°F, for a daily mean of 68.6°F. September is 7.1°F cooler than August and 12.0°F warmer than October. September is the 4th warmest month of the year in Sterling and the 4th wettest. Across the month the normal high falls 10°F, from 84°F on September 1 to 74°F on September 30. From one year to the next September's mean temperature typically moves about 2.4°F either way (NOAA's standard deviation), so roughly two Septembers in three average between 66°F and 71°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 29%).
| Day | High | Low | Chance of 0.01 in | Chance of 0.10 in |
|---|---|---|---|---|
| September 1 | 84°F | 63°F | 29% | 18% |
| September 8 | 82°F | 61°F | 29% | 18% |
| September 15 | 80°F | 58°F | 28% | 18% |
| September 22 | 77°F | 56°F | 29% | 18% |
| September 30 | 74°F | 52°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 | 84°F | 63°F | 29% | 18% | 13 h |
| September 2 | 84°F | 63°F | 29% | 18% | 13 h |
| September 3 | 84°F | 62°F | 29% | 18% | 13 h |
| September 4 | 83°F | 62°F | 29% | 18% | 13 h |
| September 5 | 83°F | 62°F | 29% | 18% | 12 h 50 min |
| September 6 | 83°F | 61°F | 29% | 18% | 12 h 50 min |
| September 7 | 82°F | 61°F | 29% | 18% | 12 h 50 min |
| September 8 | 82°F | 61°F | 29% | 18% | 12 h 50 min |
| September 9 | 82°F | 61°F | 29% | 18% | 12 h 50 min |
| September 10 | 82°F | 60°F | 29% | 18% | 12 h 40 min |
| September 11 | 81°F | 60°F | 28% | 18% | 12 h 40 min |
| September 12 | 81°F | 60°F | 28% | 18% | 12 h 40 min |
| September 13 | 80°F | 59°F | 28% | 18% | 12 h 40 min |
| September 14 | 80°F | 59°F | 28% | 18% | 12 h 30 min |
| September 15 | 80°F | 58°F | 28% | 18% | 12 h 30 min |
| September 16 | 79°F | 58°F | 28% | 18% | 12 h 30 min |
| September 17 | 79°F | 58°F | 28% | 18% | 12 h 30 min |
| September 18 | 79°F | 57°F | 28% | 18% | 12 h 20 min |
| September 19 | 78°F | 57°F | 28% | 18% | 12 h 20 min |
| September 20 | 78°F | 56°F | 28% | 18% | 12 h 20 min |
| September 21 | 77°F | 56°F | 29% | 18% | 12 h 20 min |
| September 22 | 77°F | 56°F | 29% | 18% | 12 h 10 min |
| September 23 | 77°F | 55°F | 29% | 18% | 12 h 10 min |
| September 24 | 76°F | 55°F | 29% | 18% | 12 h 10 min |
| September 25 | 76°F | 54°F | 29% | 19% | 12 h 10 min |
| September 26 | 75°F | 54°F | 29% | 18% | 12 h |
| September 27 | 75°F | 53°F | 29% | 18% | 12 h |
| September 28 | 75°F | 53°F | 29% | 18% | 12 h |
| September 29 | 74°F | 52°F | 28% | 18% | 12 h |
| September 30 | 74°F | 52°F | 28% | 18% | 11 h 50 min |
- Normal high
- 79°FSeptember average
- Normal low
- 58°FSeptember average
- Precipitation
- 3.94 inmonth total
- Days with precipitation
- 90.01 inch or more
- Days at 90°F or more
- 3
- Daylight
- 13 h to 11 h 50 minSeptember 1 to September 30
- Days at 70°F or more
- 27
- Days at 80°F or more
- 15
- Sunshine
- 76%of clear-sky sunlight (NASA)
Source: NOAA NCEI 1991-2020 daily normals, station USW00093738; monthly normals. Daylight is computed from the place's latitude with NOAA's solar equations.
Does it rain in Sterling in September?
On a given September day the chance of 0.01 inch or more is 29% on average, highest around September 1 (29%). In all, 3.94 in falls on 9 days of a normal September, 1 of them with an inch or more.
In a normal September in Sterling, 3 days reach 90°F.
Source: NOAA NCEI 1991-2020 daily and monthly normals, station USW00093738.
How humid and windy is Sterling in September?
At 3 p.m. the normal temperature is 72°F with 51% relative humidity and a dew point of 53°F; at 6 a.m. it is 56°F with 89% humidity. The wind averages 6.0 mph, most often from the west-northwest in the afternoon.
| Time | Temperature | Dew point | Humidity | Wind | Clear or few clouds |
|---|---|---|---|---|---|
| 6 a.m. | 56°F | 53°F | 89% | 4.3 mph | 42% |
| 9 a.m. | 63°F | 54°F | 72% | 6.9 mph | 42% |
| noon | 70°F | 54°F | 56% | 8.5 mph | 36% |
| 3 p.m. | 72°F | 53°F | 51% | 8.8 mph | 35% |
| 6 p.m. | 67°F | 54°F | 62% | 6.4 mph | 44% |
| 9 p.m. | 61°F | 55°F | 78% | 4.7 mph | 51% |
Source: NOAA NCEI 1991-2020 hourly normals, station USW00093738. 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 Sterling?
The warmest September temperature on this station's record (since 1960) is 100°F, on September 6, 2023; the coldest is 30°F, on September 24, 1974. The wettest September brought 11.26 in (1975).
The September mean against the 1991-2020 normal of 68.6°F: 2021 70.0°F (+1.4), 2022 69.3°F (+0.8), 2023 71.3°F (+2.8), 2024 68.9°F (+0.3), 2025 70.2°F (+1.6), 2026 71.5°F (+2.9). 6 of 6 ran warmer than normal.
| September | Mean | Against normal | Precip. |
|---|---|---|---|
| 2021 | 70.0°F | +1.4°F | 4.72 in |
| 2022 | 69.3°F | +0.8°F | 3.28 in |
| 2023 | 71.3°F | +2.8°F | 6.65 in |
| 2024 | 68.9°F | +0.3°F | 3.27 in |
| 2025 | 70.2°F | +1.6°F | 1.22 in |
| 2026 | 71.5°F | +2.9°F | 3.80 in |
Source: records: ACIS, station USW00093738; recent months: ACIS, station USW00093738. Records and recent months use complete months only.
How does September in Sterling compare across Virginia?
Across the 81 places PlainClimate covers in Virginia, September normal highs run from 73°F in Floyd to 85°F in Chesapeake; Sterling's is 79°F.
Source: NOAA NCEI 1991-2020 monthly normals for every station in the state.