Las Vegas may have seen its final 100-degree day of 2026

Las Vegas reached 100 degrees Monday. It might be the last 100-degree day of the year.

Harry Reid International Airport hit the century mark at 4:24 p.m., said Jenn Soulat, a meteorologist at the National Weather Service office in Las Vegas.

Southern Nevada has entered a cooling-off period after near-record heat last week. Last Thursday and Friday, the airport saw 107 each day but fell just short of breaking any records.

Starting Tuesday, the daily high temperatures will slowly dip into the upper and mid-90s by Friday. The average high for mid-September is 96 degrees.

Expect “persistent southerly to southwesterly breezes, along with mainly dry conditions” for Southern Nevada this week, the weather service said in a post on X.

But don’t get too excited about permanently leaving the 100s behind.

Soulat warned that a stubborn high-pressure system over the Southwest could cause a brief spike in temperatures next weekend.

In 2025, Las Vegas saw its last 100-degree day of the year on Sept. 7. Soulat said the average last 100 degree day of any year is Sept. 18.

Weak monsoon season

The monsoon season, which began in late June and lasts through September, has been almost nonexistent for the valley during a very dry year.

The airport registered a trace of rain Sept. 6 but it has seen no measurable rain this month. The average September precipitation for Las Vegas is 0.32 inches. Last year, the valley recorded 0.28 inches.

In August, the airport recorded 0.18 inches of rain, its wettest month since February (0.35). But the August average is 0.32. Reid has registered 0.69 inches of precipitation so far in 2026.

Reid saw no measurable rain in July. On June 23, the airport recorded 0.02 inches of rain, breaking a rainless streak of 124 days. It was the only rainfall of the month.

Summer heat facts

— Last month was the warmest August on record, with an average temperature of 96.3 degrees, beating out 2020 (95.6).

— On Aug. 1, Las Vegas saw 115, its hottest day of the year.

— July was the third warmest on record, with an average temperature of 96.6.

— Las Vegas recorded its first 110-degree day of the year on July 8.

— June was the seventh-warmest June on record, with an average temperature of 91.1 degrees.

— Las Vegas hit 100 degrees for the first time this year on May 8.