Natural gas futures on Wednesday soared past $9.000/MMBtu for the first time since 2008 amid worries that fragile supplies may prove inadequate to meet summer cooling demand and robust calls for U.S. exports.

At A Glance:

Traders through most of the year also have bought aggressively ahead of the prompt month’s final settlement, preferring to bet on bullish momentum given the supply/demand imbalance concerns. At its intraday peak Wednesday, the front month hit $9.399.

The June Nymex gas futures contract, a day before rolling off the books, later gave back some of the gains in afternoon trading...