(Adds quote, details on Indonesian supply and share price...

(Adds quote, details on Indonesian supply and share price movement)

SYDNEY, July 13 (Reuters) - Australia's Whitehaven Coal Ltd (WHC) said on Thursday it produced 20.8 million tonnes of saleable coal in the financial year-ended June 30, falling slightly short of guidance.

Whitehaven, which produces both thermal and metallurgical coal from three mines in New South Wales state, had set full-year production guidance of 21 million to 22 million tonnes for the year.

Coal miners earlier this year enjoyed a temporary spike in the prices of metallurgical and energy coal, which peaked in early April at $314 a tonne and $89 a tonne respectively before subsiding to finish flat quarter on quarter.

"Indonesian supply continues to be impacted by weather-related delays, which supports expectations that thermal coal prices will remain in a relatively narrow range around current levels in the near term," the coal miner said in its release of full-year operating data to the Australian bourse.

Spot metallurgical coal prices were stabilising and were expected to remain around current levels in the near term, it added.

Shares of Whitehaven slumped to a more than nine-month low in May before paring some of the losses in June on gains in coking coal prices.

The company said it expects to sell about 1 million tonnes of metallurgical coal in the September quarter. It did not give an outlook for thermal coal sales.

Managed coal sales for the June quarter, excluding sales of purchased coal, were 5.4 million tonnes, up 5 percent from a year ago.

The company said sales for the quarter were below expectations due to a train derailment, a slower than expected recovery from rail line maintenance and some port congestion.