FORSYTH COUNTY — We may not know what the weather will be a week from now, but thanks to a forecast from the Atlanta Regional Commission we have a well-educated prediction for what Forsyth County and the metro region will look like in 25 years.

Forsyth’s population is expected to more than double, to 430,300, by 2040, according to the ARC’s regional forecast its releases every four years.

If that prediction comes to fruition, it would be the fastest growth rate in the 20-county Atlanta region and the only county to double in size.

According to information from the ARC, Forsyth’s population in 2015 was 206,701.

As the population grows and the years pass, the share of the county’s population that is 65 and older is expected to increase from 11 to 18 percent, said Jim Jaquish, a spokesman for the ARC.

“They don’t want to drive as much, so that puts a different type of strain on resources. So there will have to be a bigger move for more public transport and things like Uber and taxis,” Jaquish said.

He said plans still in the discussion phase call for more transit lines reaching farther north from Atlanta “at least to maintain the level of congestion, if not improve it.”

Another forecast is that Forsyth will become more diverse, as its Hispanic population will triple, to more than 66,000, by 2040.

“The baby boomers and Eisenhowers in this region … are primarily white and black,” Jaquish said. “And that’s the group that’s getting older.

“In general, those groups are not having as many children as they used to. They’re having smaller families in general. So as Hispanics move here with larger families, there will be more of them.”

Only Gwinnett and Fulton counties are expected to add more people by 2040.

Forsyth’s predicted 108.2 percent change is followed next by Barrow County at 80.7 percent.

The 20-county Atlanta region will add 2.5 million people by 2040, bringing the region’s population to more than 8 million.

The region is also expected to add more than 1 million jobs in that time, with the top employment sectors being health care, retail, education and professional and scientific.

“The Atlanta region will remain a desirable place to live, thanks to our low cost of living and a strong economy that continues to create jobs,” said Mike Alexander, director of ARC’s Center for Livable Communities. “We’ll see growth in existing suburban areas as well as the region’s core, as more people choose to live near jobs or transit.”

This outlook is not a new one.

Frank Norton Jr., a real estate and insurance agent in Gainesville, issued the same sentiments at the county’s annual Economic Outlook Breakfast in January.

These predictions come at the right time for Forsyth in its ability to prepare for the future, said James McCoy, president and CEO of the Cumming-Forsyth County Chamber of Commerce.

“There are communities anywhere in this country who would love to be growing and in our situation and enjoy the prosperity that that brings,” he said.

He said Forsyth has long been focused on advanced manufacturing and working with western European companies, and he expects that to continue.

“The county just finished visioning committee meetings [for the new comprehensive plan], and now we’re moving into actual land use planning, and at the end of the day that document is the single most important way that everybody can be engaged in how we plan for that future,” McCoy said. “This is a phenomenal opportunity for us as a community in every aspect of this to engage in a positive, forward-thinking community conversation about what we want.

“We don’t get an opportunity to do that in any facilitated way very often, but the comp plan certainly is that opportunity.”

He said the visioning committee meeting he attended had about 30 citizens attend.

“Folks enjoy complaining about traffic and this and that. But very few — in fact, almost no one — are willing to step forward to do anything about it,” he said. There are very few places in the world where your government asks you to engage in their plan, and they mean it.

“If people don’t show up for this, it’s putting an awful lot of power into a very small group of hands. If you think about what we’re asking those 30 folks to do on behalf of 220,000, that’s shocking.”