Official White House Photo by Pete Souza

ABC News' Stephanie Smith reports:

President Obama told supporters in a conference call today that he regretted they wouldn't be able to see him in person delivering his acceptance speech in Charlotte, N.C., on this final night of the Democratic National Convention.

Sixty-five thousand ticket holders learned Wednesday that the location for the president's speech had to be moved from a large outdoor stadium that holds 75,000 to a much smaller, indoor arena because of the threat of bad weather.

"It was a safety issue," the president said in the five-minute call. "I couldn't ask you to subject yourselves to severe thunderstorms."

Obama called the situation "disappointing" and thanked those supporters, many of whom received their tickets by volunteering for the Obama campaign, registering voters, among other duties.

Watch our ABC News/Yahoo News Convention Show LIVE tonight, 7-11:30 PM HERE.

The president encouraged supporters to find a community watch party in their area so they could view his primetime speech together with other supporters.

"My main message is we can't let a little thunder and lightning get us down," he told listeners. "We just have to roll with it."

To make it up to them, Obama promised his team would get them into one of his upcoming campaign events as he travels around the country in the next two months.

"I hope to get to see all of you," he said. "Hopefully, you'll have a closer, front-row seat."

President Obama also briefly talked about the ongoing convention - tonight being the last day of the 3-day gathering - praising the many speakers and saying that Wednesday night's nominating speech by Former President Bill Clinton "broke down the issues as effectively as anyone could."

He implored grassroots supporters to work hard, acknowledged that this is going to be a close election and asked them to talk about his accomplishments and vision "in clear contrast to what we saw in Tampa" - referring to the Republican convention held that Florida city last week.