Climate averages 1991–2020
Cary weather
in September.
A warm, wet month: the 4th warmest and the wettest of the year.
Long-term climate patterns, not a forecast for a particular trip.
September is a warm month in Cary: daytime highs average 26.6°C and nights cool to about 18.2°C. By daytime temperature it is the 4th warmest of the 12 months.
Expect about 120 mm of rain on roughly 10 days, which makes September a wet month (the wettest month of the year). Daylight, from sunrise to sunset, lasts about 12 h 26 min on an average September day.
The nearest other city in this atlas is Raleigh (13 km away). In September its highs average 26.9°C, about as warm as Cary, with 120 mm of rain.
Among the 498 cities listed in the United States, Cary ranks joint 255th of 498 for the warmest September highs and joint 445th of 498 for the driest September (rainfall, lowest first). The mean September high of those 498 cities is 26.9°C; Cary is 0.3°C cooler than that mean.
From September to October, average highs fall by 5.4°C to 21.2°C, and monthly rainfall falls from 120 mm to 79 mm.
The annual picture
September in context
Monthly rainfall
Average total · mmAverages from hourly ERA5 reanalysis data. Actual weather varies from year to year. How these numbers are calculated
Every month, side by side
Cary climate table
| Month | Average highHigh / low | Average low | Rainfall mm/month | Rain days ≥1 mm/day | Daylight hours/dayDaylight h/day |
|---|---|---|---|---|---|
| January | 9.5°C0.9°C | 0.9°C | 93 | 9.3 | 10.010 h |
| February | 11.6°C2.0°C | 2.0°C | 81 | 9.1 | 10.911 h |
| March | 15.7°C5.3°C | 5.3°C | 104 | 10.3 | 11.912 h |
| April | 21.0°C10.3°C | 10.3°C | 90 | 9.1 | 13.113 h |
| May | 25.3°C15.2°C | 15.2°C | 90 | 10.4 | 14.014 h |
| June | 29.2°C19.7°C | 19.7°C | 103 | 12.1 | 14.515 h |
| July | 31.0°C22.0°C | 22.0°C | 116 | 15.2 | 14.314 h |
| August | 29.8°C21.1°C | 21.1°C | 111 | 12.4 | 13.514 h |
| September, selected | 26.6°C18.2°C | 18.2°C | 120 | 10.2 | 12.412 h |
| October | 21.2°C12.1°C | 12.1°C | 79 | 7.2 | 11.311 h |
| November | 15.5°C6.4°C | 6.4°C | 85 | 7.7 | 10.310 h |
| December | 11.2°C2.7°C | 2.7°C | 90 | 9.1 | 9.810 h |
Rainfall is the average of the 30 separate monthly totals. A rain day is a local calendar day with at least 1 mm of precipitation. Daylight is the calculated sunrise-to-sunset length, not measured sunshine.
Compare places
September in nearby cities
- Raleigh in SeptemberUnited States · 13 kmHigh 26.9°C · Low 18.4°C · 120 mm rain
- Durham in SeptemberUnited States · 25 kmHigh 26.9°C · Low 17.9°C · 112 mm rain
- Fayetteville in SeptemberUnited States · 83 kmHigh 27.6°C · Low 19.0°C · 128 mm rain
- Greensboro in SeptemberUnited States · 96 kmHigh 26.2°C · Low 17.1°C · 105 mm rain
- High Point in SeptemberUnited States · 112 kmHigh 26.3°C · Low 17.1°C · 105 mm rain
- Greenville in SeptemberUnited States · 129 kmHigh 27.0°C · Low 19.0°C · 132 mm rain
- Winston-Salem in SeptemberUnited States · 136 kmHigh 26.4°C · Low 17.0°C · 101 mm rain
- Concord (North Carolina), United States in SeptemberUnited States · 168 kmHigh 27.2°C · Low 18.1°C · 103 mm rain
Read the numbers correctly
Climate, not a promise.
These patterns help compare months. They cannot tell you the weather on a specific day of your trip.
Sources, method and limitsHow these numbers are made (what the highs, lows and rain days mean, the sources and the model cell used for Cary) is explained once on the Cary year overview and on the Sources, method and limits page.
Raleigh lies in the same rainfall cell, so its rainfall figures are identical to these; temperatures differ because they come from smaller 0.1° cells.