Arch Coal (ACI) has tacked on more than 9% this afternoon following a stronger-than-expected earnings report. The firm reported that second-quarter net income more than tripled to $113 million, or 78 cents per share, while revenue increased 31% to $785.1 billion. Analysts had predicted earnings of 64 cents on revenue of $737 million.

The shares have skyrocketed today, but the rally has been halted by the security's declining 10-day moving average. The stock's 10-day and 20-day moving averages have ushered the shares lower since July 2, resulting in a loss of roughly 25%. In fact, the stock is poised to suffer its second consecutive close below its 20-week moving average a feat not suffered since September 2007.

While the shares may have put in a strong performance today, they're still not out of the woods, remaining in a intermediate-term downtrend. At the same time, sentiment toward the shares is relatively optimistic. The Schaeffer's put/call open interest ratio for ACI is lower than three-quarters of all those taken during the past 52 weeks. Furthermore, Wall Street is quite optimistic, with 8 of the 13 analysts following ACI giving it a "buy" or better. Any potential downgrades should the stock fail to overcome resistance could weigh on the security.