Today, the star athletes of the NTT INDYCAR SERIES take a major step toward the 105th Running of the Indianapolis 500 presented by Gainbridge by setting most of the field for the May 30 race in Crown Royal Armed Forces Qualifying at Indianapolis Motor Speedway.

In “Fast Friday” practice, where teams received elevated boost levels in the engine turbochargers, drivers were reaching no-tow speeds faster than 230 mph.

Alexander Rossi appears to be a hot favorite for the NTT P1 Award for pole. 2016 Indy 500 winner Rossi led the field Friday in no-tow speeds in the No. 27 NAPA AUTO PARTS/AutoNation Honda with a best lap of 231.598 mph. Following him on the no-tow list were Graham Rahal in the No. 15 United Rentals Honda at 231.518 mph and Pato O’Ward in the No. 5 Arrow McLaren SP Chevrolet at 231.510 mph.

Six-time and defending NTT INDYCAR SERIES champion Scott Dixon will be the first driver to roll out for qualifying this morning after Team Manager Mel Harder drew P1 for the 2008 Indy 500 winner. That will give the advantage of presumably the coolest track temperatures for Dixon, who also had the fourth-fastest no-tow speed Friday at 231.502 and is a leading favorite to claim his fourth career Indianapolis 500 pole.

Defending Indy 500 NTT P1 Award winner Marco Andretti rolls off second, with 2014 Indy 500 winner Ryan Hunter-Reay third, three-time race winner and four-time pole winner Helio Castroneves fourth and Ed Jones fifth.

The action starts at 9:30 a.m. (ET) with a one hour Indianapolis 500 practice session, live on Peacock Premium. Then, Crown Royal Armed Forces Qualifying can be seen live on Peacock Premium from noon-6 p.m. Live coverage can also be seen on NBC from 2-3 p.m. and on NBCSN from 3-6 p.m.

Here’s what you need to know to be ready for today’s qualifying session.

This Is No Walk in the Park

The four-lap, 10-mile run to qualify for the Indianapolis 500 is one of the most daunting challenges in motorsports.

Thirty-five drivers will try to put together four perfect laps that feature 16 corners at speeds faster than 230 mph just for a shot at one of 33 spots in the field for the Indianapolis 500. Even the slightest tick of the steering wheel or gust of wind can drop a driver’s speed. These drivers must be perfect.

They also must be consistent. This isn’t a one-or-two-lap run. These drivers must go all-out for four laps to try to make the field for “The Greatest Spectacle in Racing.”

In practice for the Indianapolis 500, drivers struggled to put together four laps near the same speed, so consistency could be hard to find this year. Part of that was due to heavy traffic, which won’t be an issue today in single-car qualifying. But part was the challenge of riding the lightning bolt when the cars are trimmed out for pure speed.

Watch The Weather

The drivers are in for a warm afternoon in Speedway, Indiana, with highs in the mid-80s and wind gusts coming in just under 10 mph. The humidity is expected to be around 40 percent when qualifying beings at noon (ET) and is expected to fall to 36 percent by the time qualifying ends at 5:50 p.m.

The cooler the conditions, the faster the race cars. In turn, a hotter racetrack will have less grip and result in slower speeds. That’s why Friday’s qualification draw was so important. The earlier in the session these athletes hit the track, the better chance they have at making the Fast Nine Shootout.

Weather also will be the battle within the battle later in the afternoon once every driver in the field has made a four-lap attempt and the session opens for anyone to make additional qualifying attempts.

Do you want to go out earlier in the afternoon when there may be more cloud cover? Or do you want to go back out late in the session when the sun is beginning to drop in the sky, and track temperatures might be cooler? Keep in mind, at any time a cloud could move in front of the sun and cool the racetrack, or wind might pick up in a certain direction that would be optimal for a qualifying run.

As you can see, qualifying for the Indianapolis 500 is…complicated.

Qualifying, Explained

Today, all 35 drivers attempting to qualify for the Indianapolis 500 will be guaranteed one four-lap attempt. From there, the session will open for all drivers to make as many qualifying attempts as time permits.

At the end of the day, drivers who clock in average speeds from positions 10-30 will have their starting spots locked in. The fastest nine entries are locked into the Fast Nine Shootout on Sunday, while the drivers between 31-35 will move on to Last Chance Qualifying on Sunday, where two drivers will be bumped from the field.

Now, back to that question about cloud cover and wind gusts.

Pit lane will feature two lanes for teams to put their cars into: the normal lane and the fast lane. Any team looking to improve their qualifying time without withdrawing their established time will enter the normal lane.

But, if a team wants to rush out onto the track to catch the perfect conditions, or to beat the clock at the end of the day, they can choose the fast lane. However, a car in this lane with an established time must withdraw the time before making the next four-lap run.

Obviously, this comes with some risk. Sometimes the reward pays off, sometimes it doesn’t.