INDIANAPOLIS -- In a morning event operations briefing at the Indianapolis Motor Speedway media center, track president Doug Boles told reporters track and race officials are tracking a potentially severe storm that may include lightning and is likely to impact the start of Sunday's Indianapolis 500.

Here's what you need to know from Boles' morning update:

Where is the storm right now?

As of 6:20 a.m. ET, the first of two waves of storms tracking to hit IMS was around St. Louis. According to the weather experts working with the track, that storm is likely to hit between noon-1 p.m. Sunday, with some light precipitation that could possibly land before the true storms hit.

As of Saturday evening, this first wave looked as if it might hit IMS in the 2-3 p.m. window, Boles said, but those models changed.

"Our plan right now is to continue to monitor that storm. We do think we're going to get some sort of weather at some point today," Boles said. "Our biggest concern isn't the rain, so much as it is the lightning and making sure our customers at the Speedway are safe.

"The next couple hours will define when that storm could hit Indianapolis, and we will want to make sure we inform our customers and let them know where we are (in terms of altering the day's schedule) to give them time to decide what they want to do -- whether they hang at the Speedway or whether they want to stay in their cars, or frankly whether they want to wait at home until they see how this weather comes together."

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IMS will be proactive about lightning threats

Though fans may be familiar with the typical 8-mile rule (lightning within that radius can temporarily postpone or cancel youth sporting events), IMS says it will make calls to clear the grandstands much quicker.

Boles said weather radars will be shown on video screens around the property so that fans can monitor and act accordingly.

"As we start seeing this storm develop, we'll start thinking about asking folks to leave the grandstands much, much earlier than an 8-mile radius, so they can implement their own safety plan," Boles said. "We've got another 120 minutes as we see how this storm develops, and then we'll make another decision on what the right thing to do is to keep our customers safe."

IMS will alert fans on weather and venue updates through its public address system and on its video boards. Fans can also text 'Indy500' to 67283 to have alerts sent to their phones.

What does this mean for Indy 500 start time?

With a scheduled 12:45 p.m. ET green flag and rain possibly arriving by noon, there's a clear chance the 500 will not start as scheduled, Boles said. Saturday night, IMS, NBC and its partners discussed moving the race start to 12:15 p.m.

"But when it started to look like that storm could hit at noon, it didn't make any sense to do that," Boles said. "And the last thing we wanted to do was to move it up to 12:15 p.m., have customers come here waiting for the pre-race ceremonies, and then sometime before that tell them that they need to leave for the weather.

"When it looked like these storms could hit us as late as 2-3 p.m., (moving up the start) 30 minutes could've really helped us, but because of where this is tracking, it doesn't make sense to move it at all because we'd just put ourselves in a worse position."

What will happen to Indy 500 pre-race ceremonies?

Driver introductions are set to being this morning at 11:47 a.m., just under an hour before the scheduled drop of the green flag. The sentimental portions kick off at 12:11 p.m. with "America the Beautiful," and that's where Boles said the program is likely to get cut off.

"The part that's most important to folks is the last half-hour," Boles said. "You start thinking back from the "command (to start engines)" backwards. I think by 9:30 a.m. we'll definitely have a decision made on where we're going with those elements. If it's just rain, we'd typically go through pre-race up to a normal stopping point which is before those last important parts of the cadence and then move to those whenever we get closer to the race start or restart.

"So it's just about how much of the other stuff we put a hold on."

Boles: 'Make decisions to keep you the safest'

Boles closed with this message to fans:

"We're asking our customers to think about 'Where do I park? How comfortable am I?' Some may not be comfortable sitting in the grandstands for a long time before this situation arises. Think about where you're parking and where you are right now. Maybe where you are right now isn't IMS and you want to sit and wait. Those pieces are important because this place is so big.

"We're asking our customers to look at the weather, watch the radar, listen to where we are and make a decision that's going to keep them the safest. This storm is pretty easy to see. You can see the red in this storm. We hope it parts or goes away by the time it gets here, but this is not going to be a pop-up storm.

Boles also said race officials weren't going to get too preoccupied with weather watches or warnings when it comes to making decisions Sunday morning. The next one, he said, should come by 10 a.m.

"I see a big red blob coming here. It's got lightning in it, and the most important thing we can do is inform fans and stay on top of that," Boles said. "We're relying on what we see in real-time to make sure we can make the best decisions for our fans, regardless of what someone else thinks."

This article originally appeared on Indianapolis Star: Indy 500, weather, start time, lightning, safety and more