It has been a cruel summer for natural-gas investors. Gas prices were buoyed in early June by low supplies and the prospect for a hot summer, which would boost demand for the fuel. But temperatures have been tepid, with weather forecasts through the end of August turning cool. Prices have lost 20% since mid-June, ending Friday at $3.776 a million British thermal units on the New York Mercantile Exchange, a nearly three-week low. If the end-of-summer outlook holds true, it will serve as a fitting coda to a mild season that has kept demand in check and allowed producers and utilities to rebuild inventories badly depleted last winter. Utilities burn natural gas to generate electricity, and a hot summer can boost demand for gas to run air conditioning in homes and businesses. In the winter, natural gas is used to warm more than half of the homes in the […]