How will warm fall weather affect Balloon Fiesta?

Goodbye, monsoon season. Hello dust — and a warm Albuquerque International Balloon Fiesta.

The first day of October ushered in warmer than average weather, but a cold front from northeastern New Mexico will bring a slight drop in temperature just in time for the Balloon Fiesta, forecasters say. But the weather still will be warmer than normal for the season.

Why does the heat matter?

Albuquerque is the hot spot for balloonists, mostly because of a weather phenomenon known as the “Albuquerque Box” — a predictable atmospheric wind pattern that creates easy-to-navigate winds for balloonists. Balloonists use the box to fly in a box-like flight pattern, which makes it easier to estimate where landing zones will be. It also allows for more balloons to launch simultaneously, during mass ascensions, for example.

Temperatures in the Albuquerque area are forecast to remain well above normal during the Balloon Fiesta, which runs from Saturday through Oct. 13, with little or no chance of precipitation expected. The air temperature in the balloon must be higher than the air temperature outside of the balloon to achieve buoyancy.

“Sometimes that can change the air density, and that makes it a little harder for balloonists to get the balloons to rise,” said meteorologist Todd Shoemake of the National Weather Service. “In the morning time, it’s still dry, so temperatures will be cool but not as cool as what they should be. It’ll probably still be 10 degrees above what it should be.”

Balloonist Karalyn Mumm said while the warm weather makes it easier to get up in the morning, balloons might not fly for as long because they need more propane to keep the balloons aloft.

“In order for the balloons to fly, we need to get the air in the balloon hotter than outside,” Mumm said. “If it’s warmer outside we have to increase that amount of propane we use and that can make for shorter flights. We only carry a finite amount of propane in the balloon with us.

“I’ve flown for two hours in Albuquerque and I’ve flown for 45 minutes — and that depends on a lot things, but sometimes it’s warmer and you use up that propane faster.”

Density altitudes will also be higher as a result and pilots have to take those numbers into consideration when flying. High density altitudes can affect the performance of aircraft, making it harder to climb high in the air. Mornings are still expected to be chilly with temperatures estimated between 50-60 degrees, but Fiesta-goers might not have to bundle up as much as in previous years.

“The warmer weather makes it nice and as the morning goes on it gets better, but we prefer the cooler weather because it allows us to fly a little bit longer,” Mumm said.

Why is it warmer than normal?

In the Albuquerque metro area, remnants of a cold front from eastern New Mexico will bring temperatures down from the 90s to the mid-to-high 80s.

Gusts also bring an increase in fine particles like dust or pollen, which can affect air quality. On Tuesday, the city of Albuquerque issued a health alert warning residents about blowing dust. People with respiratory issues were recommended to limit outdoor activity whenever possible.

Monday hit a record high of 93 degrees — the normal high this time of year is typically 77 degrees.

“Lots of places have been temperatures above average the last four years or so,” said meteorologist Shoemake. “That’s even extending out into a lot of the Southwest, like Phoenix. It really comes down to an area of high pressure and that’s been really strong over a lot of the American Southwest. That’s one of our features of the monsoon and the high pressure is hanging tough, so any kind of tropical systems can’t really come up our way.”

Areas of high pressure also explain why temperatures are still high going into October.

“It kind of chokes out the moisture and puts a lot of warm air aloft into the atmosphere, so it’s a lot harder to get thunderstorms to build up. We had a few that tried to go up the other day, but they fizzled out,” Shoemake said. “So all fingers are pointing to high pressures as the culprit of that.”