More Americans are opting to move south, favoring beaches and warmer climates over snowy winters.

New Census data suggest most of the nation’s fastest growing metro areas are retirement destinations found in the Sun Belt.

Many Sun Belt retiree hotspots had seen slowdowns in migration during the economic downturn. But the latest Census data numbers signal that, for the past two years, migration to these regions has largely accelerated again. The reversal is perhaps most evident in Florida, a state that last year had eight of the nation's top 10 metro areas with the highest net migration rates.

The new population estimates for the 12-month period ending last July cover all metro areas and counties. Of larger metro areas with more than a million residents, regions recording the highest annual net migration rates were Austin-Round Rock, Texas, (+206 per 10,000 population); Orlando-Kissimmee-Sanford, Fla., (+205 per 10,000 population); and Tampa-St. Petersburg-Clearwater, Fla. (+183 per 10,000 population).

In terms of raw totals, the Houston (+99,260) and Dallas-Fort Worth-Arlington (+86,701) metro areas registered the top total net migration gains in 2015. The four largest metro areas in Texas, in fact, collectively added more residents last year than any other state.

One region that’s recorded steady population growth from domestic migration each of the past few years is the Myrtle Beach-Conway-North Myrtle Beach, S.C., area. Parts of North Carolina also benefit somewhat from retirees, although not to the same degree as coastal regions further south.

“To some extent, retiree migration into North Carolina is very new,” said Rebecca Tippett, who studies demography at the Carolina Population Center. “It really started to uptick in the last 15 years.”

Not all retirees flock to the Carolinas or elsewhere in the Southeast from colder climates, however. Some initially move to Florida, then opt to relocate in search of more seasonal weather, mountains or other amenities, Tippett said. These retirees have been dubbed “halfbacks”: After first moving south, they ultimately end up moving back north -- but not all the way.

Migration across the Southeast isn’t exclusively tied to movement of retirees. The Raleigh, N.C., and Charlotte, N.C., regions attract younger adults with large research institutions and major employers. Some growing metro areas, Tippett said, also benefit from those wanting to live closer to high-quality medical facilities and caregivers.

The population shift to the Sun Belt should continue as more baby boomers retire, although another downturn in the economy would likely slow its momentum.

Several Sun Belt metro areas recently rebounded after experiencing large migration dropoffs during the years immediately following the Great Recession.

Consider the Phoenix metro area, which has recorded net domestic migration gains exceeding 40,000 each of the past two years after adding only about 3,000 residents in 2010 and 4,000 in 2011. The Las Vegas-Henderson-Paradise, Nev., area similarly lost residents via domestic migration in 2010 through 2011, but saw nearly 25,000 people migrate in from other parts of the U.S. last year. Both regions were hit particularly hard by the bursting of the housing bubble. Other metro areas experiencing notable upticks in domestic migration recently include the Atlanta and Tampa metro areas.

Areas relying more on retirees tend to experience little to no natural population changes (that is, deaths subtracted from births), a characteristic quite common throughout jurisdictions along coastal Florida. This graph illustrates five retiree-driven Sun Belt metro areas where domestic migration has accelerated:

Jurisdictions experiencing sizable population shifts must plan and budget accordingly. Hillsborough County, where Tampa is located, has focused on improving its transportation network to accommodate the region’s projected growth. The issue is likely the most important facing the region, so officials are budgeting additional dollars for transportation projects, said Liana Lopez, the county’s chief communications administrator. Hillsborough County welcomed an estimated 15,000 residents from other parts of the country last year after recording slight domestic migration losses in 2012 and 2013.

Movement to the Sun Belt has, in turn, taken a toll on Snow Belt regions. Net domestic migration in Sun Belt states nearly matched its 2004-2005 peak of 600,000 last year, according to the Brookings Institution’s William Frey. Meanwhile, in northeastern states, Census estimates indicate that total population loses stemming from domestic migration topped 324,000.

In Chicago, the metro area's total population dipped by just over 6,000 last year. While that’s not much given the region's size, it marks the first annual population decline in years. Cook County, the region’s largest county, lost population for the first time since 2007.

The El Paso, Texas, metro area recorded the lowest net migration rate of any metro area with more than 500,000 residents from 2014 to 2015. El Paso has registered negative net migration for four consecutive years, losing just under 12,000 residents last year.

Along with domestic migration, movement to and from foreign countries further influences migration rates. Every metro area recorded positive gains from international migration last year, helping to offset continued domestic losses in places like New York City that lose residents to other regions each year. A recent analysis of Census data suggests the foreign born are increasingly settling in less-established immigrant cities where their numbers are fewer.

Metro Area Migration Data

Figures shown reflect changes in Census population estimates between July 2014 and July 2015. Total migration estimates include domestic and international migration.