After a two-day rally that added roughly 40 cents to the price of September natural gas, Nymex futures stalled Wednesday as recent cooler shifts in the weather data were too much to ignore. The September Nymex contract settled two-tenths of a cent lower at $2.191. October was nearly unchanged at $2.331.

Spot gas prices also showed signs of cracking, with NGI’s Spot Gas National Avg. down 1.0 cents to $1.910.

Analysts agreed that fundamentals hadn’t changed enough to warrant such a pronounced rally in only two days. While weather data turned hotter initially, and liquefied natural gas (LNG) volumes improved, the quick acceleration was stunning.

“But it is natural gas, and when one side has their back against the wall, price moves become extreme and irrational,” said...