There are 3 key metrics that Alexander Felice lays out in his most recent article for determining the Top 3 RE picks for up and coming markets.
State growth: Picking to invest in states that re-invest in themselves is important. The more investment a state puts into growing its economy and its communities, the more likely your real estate investment is to pay off.
Job diversity: Invest in markets with a wide breath of jobs. If there are only one or two major employers in the city, that can cause big problems for the real estate market when those employers hit a lull. Look for an array of employers and diversity in industry.
Population growth: If more people are moving into a city, that means more opportunity for the real estate market. This is probably the simplest metric to gauge an up and coming market.