Las Vegas Weather in September

In September, Las Vegas, Nevada usually sees the last of summer's 100-degree Fahrenheit temperatures (over 37 degrees Celsius).

This page gives detailed information on the typical September temperature, precipitation, sun, humidity, wind and storms for Las Vegas. The numbers here are historical averages based on climate data gathered at the McCarran International Airport, located near the south end of the Las Vegas Strip.

Temperature Weather iconTemperature

95 °F September average high 35 °C
72 °F September average low 22 °C
24 days 90 °F max. or more (32 °C)
13 days 70 °F min. or less (21 °C)

Nearly every day in September heats up to over 80 °F (26 °C) in Las Vegas. The city averages 8 days this month when the thermometer reaches into the 100s °F (over 37 °C).

At night, the thermometer dips to 60 °F (16 °C) or below on 2 days. Normally September does not get as cold as 50 °F (10 °C).

Rainy Weather iconRain

0.3 in total precipitation 8 mm
2 days of rain

Most years, Las Vegas gets less than 0.4 inches (11 mm) of rain in September. About once every four years, the city receives no rain at all this month.

Sunny Weather iconSun

91 % sunshine
22 days clear skies

The sun's rays reach the ground in Las Vegas during 91 percent of daylight hours on average in September, for a total of 338 hours in the month. Typically on 22 days this month the sky is mainly clear, with at most 30 percent cloud cover.

Sunlight in September at Las Vegas lasts for 12 hours and 22 minutes a day on average. The longest day of the month is the 1st with 12 hours and 55 minutes of daylight. By the end of the month, the days have shortened to 11:50 from sunrise to sunset. These durations can vary by a minute or two from year to year.

Humid Weather iconHumidity

25 % September average humidity

The relative humidity in Las Vegas during September usually peaks at 34 percent in the morning then drops to 17 percent around mid afternoon.

Local Time1 am4 am7 am10 am1 pm4 pm7 pm10 pm
Humidity % 30 34 32 23 18 17 21 26

Windy Weather iconWind

8.9 mph September wind speed average 14.3 kph

September is a little less windy than most other months in Las Vegas.

Stormy Weather iconStorms

1 day rainfall of 0.1 inches (2.5 mm) or more
2 days with thunderstorms in September

About once every five years, Las Vegas receives as much as an inch (25 mm) of rain in one day during September.


The weather data here are long-term averages provided by the US National Centers for Environmental Information (NCEI). Temperature and precipitation are 1991-2020 normals while humidity and thunderstorms are 1961-1990 normals.

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