Las Vegas Weather in September: Essential Climate Guide
Introduction
You would think by September the summer heat would be disappearing rapidly but you’d be wrong. Summer hangs on in Vegas much longer than people think. It is the 4th warmest month and 100s are still common in the first half of the month. It’s still even possible to get over 110F/43C. The second half of the month is usually when things really start to improve. The last 100F/38C on average is the 16th and nighttime temperatures really start to drop, providing relief at last. The monsoon can still be active in September so brief storms are possible. In this post I will detail what to expect when you visit Las Vegas in September.
Be sure to see how I ranked this month for best month to visit at the end!
The Las Vegas Strip
Quick Stats
4nd warmest month
4th driest (tied with 2 other months)
9 days above 100F (38C).
Normal highs range from 100F-89F (38C-32C)
2 days of rain
Warmest ever 114F (46C) - Coldest ever 43F (6C)
Most rain in a day 1.18”
5th least busy month* (Source: LVCVA Research Center)
Temperatures
I know from experience it seems like summer will never end in Las Vegas. The first half of September is just a continuation of the desert heat. There are still 9 days over 100F/38F this month and most of which are in the first half. And 14 times it has even still got to 110F/43C, 5 of which were in the last five years. Summer is definitely hanging on longer. What really makes September such a relief is the overnight lows dropping from near 80F/27C at the beginning of the month to a refreshing 66F/19C at the end.
I find the best way to get a feel for the weather is by looking at what happened in a previous year. Here is the latest actual September temperatures (2023).
September 2023 was what I would call typical with 100s early on but major relief by the end of the month. Even a 74F/23C high on the last day of the month!
Rainfall
With tropical activity still going strong in the eastern Pacific off of Mexico, some of that moisture still manages to find its way north to the Mojave Desert. There are 3 days this month with rain although the total is tied for 4th driest. Still, 17 times Las Vegas has experienced more than 0.50” rain in one September day. But the most intense monsoon thunderstorms have usually passed. On the other hand, more than one-third of Septembers see no rain at all. Usually this happens because the monsoon has died down or was never very active and winter storms have not yet arrived.
What To Pack
In September there’s not really much change in packing. It’s still all about keeping cool. Bring light weight, loose fitting clothing. But if you’re coming in the latter half of the month, you may need a long-sleeve or light jacket, especially at night.
Be sure to keep sun protection handy at all times. Sunglasses, hat, and sunscreen are still essential in September - especially if you will be at the pool.
Reusable water bottle
An umbrella still isn’t a bad idea this month in case there is a sudden thunderstorm. They can be hard to find on the strip after the rain starts and you may pay inflated prices.
Comfortable shoes are a must. Las Vegas involves a lot of walking, especially along the Strip. Comfortable shoes are essential to prevent getting tired and blisters.
Swimwear is necessary if you plan to take a dip.
Don’t Forget These Other Things:
A portable charger. I know from experience if you forget one it’s gonna cost you an exorbitant amount to replace it if you have to buy it on the Strip.
Remember to pack your necessary medications as well as personal care items like toiletries, hand sanitizer, and lip balm.
Don't forget to bring your ID, credit cards, travel insurance information, and any other essential documents you may need for your trip. Seems obvious but I’ve done it.
Sunrise/Sunset
Sunrise on September 1st starts at 6:12 AM. By the end of the month the sunrise is 6:35 AM. Sunset at the beginning of the month is 7:07 PM and by the end is 6:24 PM. There is about 13 hours of daylight each day starting the month and 12 hours by the end of the month. Remember, Las Vegas is in the Pacific Time Zone - same as Los Angeles.
Safety Tips
Stay hydrated: It’s starting to get hot and the desert is very dry! Drink plenty of water throughout the day to stay hydrated, even if it’s a little cool. And remember alcohol adds to dehydration. Frozen alcoholic drinks can sometimes cause stomach cramps.
Lightweight Clothing: During the daytime you’ll need lightweight and breathable clothing. Opt for materials like cotton or linen, which allow air circulation and help you stay cool.
Protect against sun exposure: The sun is still intense in September. Wear sunscreen, sunglasses, and a hat to shield yourself from harmful UV rays, especially if you’re hiking or golfing.
Know Your Limits: Las Vegas offers a wide range of distractions and people seem to forget walking outside from casino to casino can take its toll when it’s hot. Pace yourself, drink responsibly, and take advantage of air conditioning often.
Outdoor recreation becomes much safer in September. But keep in mind it’s still pretty hot and you should try and focus your activity in the morning if you can.
If you encounter monsoon thunderstorms, avoid being hit by lightning by going indoors. Many pools and outdoor attractions close with the threat of lightning anyway. If you’re driving, understand that heavy rain will just run off causing flash flooding. Do not try to drive through a flood road. Many roads outside of Vegas dip down into a normally dry wash which can fill up many feet deep and easily wash away you and your car!
Planning to visit Death Valley?
Check out my weather guide for Death Valley.
Conclusion
September is when things really being to improve, but the first half can still be very hot. And with kids back in school the number of visitors is manageable. Pools are still going strong but monsoon storms can still drop brief heavy rain. Overall, definitely not the worst month but I would rank it higher if it wasn’t for the lingering heat.
Find out the best time to visit Death Valley. All the stats on temperatures, rainfall, and extremes including flash floods.