Phoenix, Arizona: Storms Ground Flights at Sky Harbor, Delay 478 by Midday and Knock Out Power to 5,000

Thunderstorms crossing metro Phoenix on Friday, October 30, stopped air traffic at Phoenix Sky Harbor International Airport for about an hour, delayed hundreds of flights and knocked out power across parts of the Valley before the evening flood rescues began.

The Federal Aviation Administration ordered a ground stop for Sky Harbor that took effect at 11 a.m. Friday and ran through at least noon, according to the FAA's National Airspace System Status site, reported by the Arizona Republic. A ground stop holds aircraft on the ground at their departure airports instead of letting them fly into an airport where conditions are unsafe. Flights were delayed up to 60 minutes on average while the stop was in place, and a departure delay stayed in effect after the stop expired, the Republic reported.

The delay count kept climbing

By 1:45 p.m. Friday, flight tracking site FlightAware counted 478 delayed flights and four cancellations at Sky Harbor for the day, the Republic reported. The disruption grew through the evening as storms kept moving across Maricopa County. A later tally reported by KTAR News put the day at nearly 800 delayed flights and seven cancellations. Airlines, not the FAA, cancel flights; the agency's role is to hold and space traffic when thunderstorms make takeoffs and landings unsafe or when lightning drives ground crews off the ramp.

The National Weather Service office in Phoenix had put the chance of rain at 90 percent for Friday, with up to 0.75 inches possible in the first forecast the Republic cited, and flood watches covered metro Phoenix on Friday and again for the Halloween weekend. The rain that fell was heavier in places than that first estimate: between 5 p.m. and 8 p.m., parts of Paradise Valley took 2 to 3 inches and much of north Scottsdale took 1 to 2 inches, according to the storm reporting summarized from KTAR.

Power went out as the evening storms hit

The same evening storms cut electricity across the Valley. KTAR News reported that more than 5,000 Salt River Project and Arizona Public Service customers were without power at about 8 p.m. Friday. Crews restored service to most of them within about an hour, and about 1,000 APS customers were still out at 9 p.m., KTAR reported.

Friday's airport stop and outages were the first round of a wet Halloween weekend, not the last of it. The weather service has a second flood watch for Phoenix and much of Arizona from 11 p.m. Saturday, October 31, to 5 a.m. Monday, November 2. Gabriel Lojero, a meteorologist with the National Weather Service in Phoenix, told KTAR that conditions should ease for Saturday afternoon and the early trick or treating hours before the next wave of rain arrives after 8 p.m. Saturday.

Travelers flying out of Sky Harbor this weekend should check their flight with their airline before leaving for the airport, and drivers should expect flooded dips and washes after dark. Friday showed both sides of the same storm at once: planes held on the ground at midday, and power crews and firefighters working through the evening.