Sky Harbor flights delayed, canceled. Here's why and what travelers should know

Lightning strikes in the skies behind Phoenix Sky Harbor International Airport as seen from the roof of the IDEA Tempe Parking Garage on Monday, Aug. 21, 2023. Alex Gould/Special for The Republic

Flights were grounded Friday, Sept. 26, at Phoenix Sky Harbor International Airport because of severe weather, as the National Weather Service forecasted a high chance of thunderstorms.

A ground delay affecting flights to Sky Harbor took effect at about 11 a.m. Friday and was to remain through 6:59 p.m., according to the Federal Aviation Administration's National Airspace System. The FAA had a ground stop in effect at Sky Harbor in the morning that was lifted around 11:30 a.m., followed by another ground stop in the afternoon in effect through 4:30 p.m.

Flights to Phoenix were delayed for about 75 minutes on average, according to the FAA.

Sky Harbor also had a departure delay in effect, with flights from Phoenix delayed for about 15 minutes on average.

Here's what air travelers should know if they're flying Friday.

Why are flights grounded?

The FAA grounded flights at Sky Harbor because of severe weather and thunderstorms.

The National Weather Service forecasted a 50% chance of rain and thunderstorms on Friday. It stated there's a chance of torrential rainfall with localized flooding and frequent cloud-to-ground lightning strikes.

A flood watch is in effect for metro Phoenix from 8 a.m. to 11 p.m. Friday.

The stormy weather caused 15 Phoenix-bound flights to be diverted to Tucson International Airport, said Austin Wright, spokesman for the Tucson Aviation Authority. Some of those flights were cleared for release to head to Phoenix, while others were still affected by the ground stop, he said.

How many flights were delayed at Phoenix Sky Harbor?

What does a ground stop mean when flying?

The FAA can order a ground stop when it's not safe for flights to take off or land at an airport.

It can also order a ground delay, which is when flights destined for an airport experiencing adverse conditions must delay their takeoffs, according to the FAA.

The FAA can order a ground delay or ground stop, but it does not cancel flights.

What should travelers know if they're flying today?

During airport disruptions such as severe weather, staff at Sky Harbor encourage passengers to check the status of their flight with the airline they're flying before arriving at the airport.

While airlines don't yet have travel advisories for travel to and from Phoenix, airlines generally rebook passengers on the next available flight at no additional cost when a flight is canceled or delayed. Passengers can also receive a refund for the unused portion of their ticket if they choose not to travel.

Michael Salerno is an award-winning journalist who’s covered travel and tourism since 2014. His work as The Arizona Republic’s consumer travel reporter aims to help readers navigate the stresses of traveling and get the best value for their money on their vacations. He can be reached at [email protected].

(This story was updated to add new information.)