ALBUQUERQUE, N.M. (AP) — One of the world’s most photographed events begins Saturday with a colorful mass ascent for the 52nd annual Albuquerque International Balloon Fiesta.

The nine-day gathering draws hundreds of thousands of spectators and pilots to New Mexico each fall for the rare opportunity to be within arm’s reach as the giant balloons are unpacked and inflated. Propane burners roar and hundreds of the uniquely shaped balloons light up the sky in vibrant colors.

Normally everyone dresses in layers to protect themselves from the morning chill that helps pilots stay in the air longer, but this year’s fiesta could be the warmest on record, organizers say.

In a city that recorded its hottest temperatures this year, hitting 93 degrees Fahrenheit (33.8 degrees Celsius) on Monday, morning lows and afternoon highs are expected to be on days above average National Weather Service.

Things are also getting hotter around the world. It’s probably this year will end up being the warmest Humanity has measured, the European climate service Copernicus reported at the beginning of September.

Although previous festivals have seen a warm day here and there, spokesman Tom Garrity said the forecast of sustained heat is rare.

For pilots, it could mean spending less time in the air or carrying less weight in their baskets.

When the mornings are cool, less fuel is typically needed to get the balloons up. Fiesta veterans explain that it involves creating lift by heating the air inside the envelope to temperatures higher than the outside temperature.

“In cooler weather, pilots can fly longer,” Garrity said. “But when the temperatures are warmer it just means you show up, go up a little bit and then come back down. So just a few shorter flights.”

However, balloon rides are available year-round in many places, including the Phoenix area, where there have been many balloon rides Record temperatures in the last few months.

“From a spectator’s perspective, these aren’t really problems,” said Troy Bradley, a veteran balloon pilot who has been flying for decades. “I don’t see any difference except that they won’t freeze in the early hours of the morning.”

Even the festival’s official meteorologist has joked about the possibility of wearing shorts this year.

This year’s Fiesta will also feature 106 balloons in special shapes, 16 of which will make their Fiesta debut. This includes Mazu, which is modeled after the sea goddess of the same name and is deeply rooted in Taiwanese culture and tradition.