LAS VEGAS (KTNV) — The impact of smoke from the Las Vegas Valley wildfires could be felt from schoolyards to the airport on Wednesday.

In addition to prompting an air quality advisory due to unhealthy air and particulate pollution, the smoke also caused changes to Clark County School District operations and delays at Harry Reid International Airport.

Extracurricular activities cancelled

The impact of the smoky air prompted the Clark County School District to cancel all non-essential outdoor activities. School administrators were told to ensure activities such as lunch, gym and recess were moved indoors on Wednesday.

The cancellations also apply to extracurricular sports activities, which district officials said would be rescheduled.

Flights delayed at Las Vegas airport

The Federal Aviation Administration warned that the smoke could affect visibility around the airport and cause delays at Harry Reid International.

“As a result, some arriving flights are experiencing an average delay of 1 hour and 5 minutes,” the FAA warning said.

Online flight tracking service Flight Aware had documented 411 delayed flights at Harry Reid Airport as of 1:04 p.m.

Of those flights, 237 were to Las Vegas and 174 were out of Las Vegas. Most of the delays — an estimated 62 percent — were on Southwest Airlines flights.

At the time of this report, 10 flights had been canceled. Nine of those were Southwest flights.