What happened

WEC Energy Group (WEC -1.59%) stock well outperformed the market last month, rising 12% even as the S&P 500 declined 2%, according to S&P Global Market Intelligence. The energy specialist is up 33% so far in 2019.

An engineer works on an electric wire.

Image source: Getty Images.

So what

August's rally came following a generally strong second-quarter earnings report from the Midwestern utility company. Despite unusually mild weather compared to the prior-year period, WEC Energy managed to maintain nearly flat sales as operating income slipped to $315 million from $331 million. Net income ticked higher thanks to lower tax expenses.

Now what

CEO Gale Klappa and his team lifted their earnings outlook for the full year, in part thanks to the fact that WEC's customer base is expanding both in its electricity and natural gas segments. Executives now see sales landing near the high end of their raised range of  $3.50 per share to $3.53 per share, with help from falling costs.

"Our focus on financial discipline and operating efficiency were major factors driving our positive results," Klappa said in early August. Those positive trends are expected to continue lifting profits over the next six months.