As it prepares its first-quarter financials for release later this month, the Pennsylvania-based producer said it had total coal production of 17.2 million tons for the period ended March 31, including 1.5Mt of low-volatility metallurgical product from the Buchanan operation in Virginia.

The figure is the company’s highest of any financial period since the fourth quarter of 2008.

"Consol's mines ran exceptionally well during the quarter," chairman and chief executive officer J Brett Harvey said.

“As a result of the very good quarter, [the company] is increasing its annual coal production guidance from 59-61 million tons to between 60 and 62 million tons, with second-quarter production between 14.75 and 15.25 million tons.”

Consol said the guidance was a reflection of its typical seasonal production pattern, which would be higher production in the first and fourth quarters of the year than in the second and third quarters.

One factor which will also affect production numbers in the second quarter is six planned longwall moves.

Higher than anticipated production resulted in a rise in inventory for its thermal coal from 600,000t to 2.5Mt during the quarter, though low-vol inventory at the Buchanan mine remained steady versus the previous quarter at 200,000t.