Weather in United States in September
September in United States is warm outdoor weather. Days are long enough to be useful. Shade starts to matter at midday.
A country pin in September is a warning: one region of United States will not match another. Use a city page if you already know where you are going. Compared with July and January, September sits in the middle of United States's year.
- Average temp
- 20°C
14–27°C
- Rainfall
- 72 mm
Showers likely
- Sunshine
- —
- Wind
- 16 km/h
What to expect
Daytime
Warm days in United States in September. A hat starts to earn its keep at midday. Evenings are the comfortable part of the clock.
You can walk at more hours than in the fierce months. Still build in a pause when the sun is high. Nights are easy.
Rain
Mixed skies in United States in September. Dry days and wet days share the month. Outdoor plans need a backup, not a cancellation policy.
Pack a shell you will actually carry. The monthly table is the place for totals. This is the feel: usable, interrupted.
Evening
Evenings are cooler. A layer helps after sunset.
What to pack
Rain jacket
A layer for cooler evenings
Where to stay in United States
Featured stays on trip1. Dates are a starting point for September.
Travel guides for United States
What to read before you book.
Average weather in United States
TemperatureRainfall
Similar weather in September
Other destinations whose September averages sit close to this one.
Check another month
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FAQs about United States
Climate averages for United States, 1991–2020.
The best time to visit United States is between May and October, the most comfortable stretch of the year on these averages.
July is the hottest month, with an average around 26°C.
May is the wettest month, with about 112 mm of rain.
No. These are 1991–2020 climate normals from Meteostat, not a live forecast. Actual weather in any given week can differ.
