Although we don't believe in timing the market or panicking over market movements, we do like to keep an eye on big changes -- just in case they're material to our investing thesis.

What: Shares of aircraft leasing company Atlas Air Worldwide (NASDAQ:AAWW) fell 20% today after adjusting guidance.

So what: Management now expects third-quarter earnings of $1.13 per share and full-year earnings of $3.40-$3.80 per share. Analysts had expected earnings of $1.37 per share in the most recent quarter and $4.73 per share for the full year so this was far below what investors had priced into the stock.  

Now what: The airfreight peak season is weaker than expected and military cargo volumes are down as well. This has caught investors off guard but I don't think it's as bad as the market's reaction. Shares are now trading at 10 times the top end of earnings and there's clearly upside if the market improves. I think this could present a buying opportunity for investors with an eye on the long term.

Fool contributor Travis Hoium has no position in any stocks mentioned. The Motley Fool has no position in any of the stocks mentioned. Try any of our Foolish newsletter services free for 30 days. We Fools may not all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy.