When it comes to investing in stocks, volatility is par for the course. But that volatility can also be a great thing for investors who are prepared to take advantage, especially if the stocks they're watching suffer a temporary decline.

Finding the best deals, however, is easier said than done. So we asked three top Motley Fool contributors to weigh in on promising stocks that they believe are either suffering a short-term dip as we speak, or represent prime candidates to buy on a pullback. Read on to see why they chose Under Armour (UA 1.73%) (UAA 1.81%), Markel (MKL 1.43%), and Nordstrom (JWN 0.96%).

Man drawing stock chart on a brick wall.

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Run toward this deal while you can

Steve Symington (Under Armour): Shares of Under Armour have fallen nearly 50% over the past year, including a more than 30% drop so far in 2017. For that, Under Armour can thank a painful slowdown in its core North American performance apparel business, where revenue fell 1% as new distribution to retailers like Kohl's was more than offset by business lost to multiple bankruptcies last year in the sporting-goods retailer space. Revenue in the first quarter of 2017 climbed just 7% year over year, which was in line with management's expectations, but marked the first time Under Armour had fallen below 10% growth in more than 10 years.

To be fair, Under Armour isn't alone in its recent North American struggles. Shares of Nike also declined last quarter after management revealed that Nike store traffic was impacted by changing consumer patterns in North America. According to Nike CEO Mark Parker, those patterns are "driving a more promotional environment in the near term" -- which means margin and revenue pressure as athletic apparel and footwear leaders try to better position themselves to take market share while these headwinds persist. 

But we should also keep in mind that Under Armour is still driving stellar growth in international markets, where revenue climbed 52% (57% at constant currency) last quarter and still only comprised around 20% of total sales. In addition, Under Armour's direct-to-consumer (DTC) channels drove healthier 13% growth last quarter, to represent around 27% of sales.

As the fallout of retailer bankruptcy headwinds in North America begins to wane, the relative outperformance of Under Armour's DTC and international businesses should become more evident, leaving it in an even stronger position to continue taking market share globally. With shares now trading at just 1.64 times trailing-12-month sales (TTM) -- compared to around 2.59 times TTM sales for Nike -- I think investors would do well to pick up Under Armour stock while it's still cheap.

This long-term compounder is a great "buy on the dips" stock 

Jason Hall (Markel): Markel's insurance operations are its biggest business, and its earnings can swing from quarter to quarter, particularly if natural disasters affect its results. But at the same time, a single bad quarter for something that every insurer faces from time to time shouldn't cause investors to worry. Furthermore, its share price can also decline when the rest of the market sells off -- and very often, for no specific reason that has anything at all to do with Markel's business results or prospects. 

Instead of letting these things frustrate you, or scare you into selling, it's a much smarter move to take these opportunities to buy more of this wonderful company. 

This is especially true for investors truly focused on the long term. Markel is a unique opportunity to buy a company with one of the best capital allocators out there in Tom Gayner. For decades, Gayner has been Markel's primary investing officer, picking which stocks the company would invest in. More recently, he has been involved in choosing the operating companies it would acquire for its growing Markel Ventures segment. 

This makes Markel a wonderful company to own for the long term. It's also an excellent stock to keep on your watchlist, with an eye on buying more when the market puts it on sale. 

This retailer could grow again

Dan Caplinger (Nordstrom): The retail industry has faced a huge struggle recently, and the luxury end of the retail spectrum, in particular, has suffered some major disruptions that have threatened many stalwart stocks. Nordstrom has a reputation for unparalleled customer service and high-quality merchandise, but even it has seen a downturn in its full-line premium department stores as a result of the poor industry environment. In its most recent quarterly report, Nordstrom took a 6% hit on comps within its premium stores, and better performance in online sales only made back part of that deficit.

However, Nordstrom is working hard to adapt to changing conditions. Its off-price Nordstrom Rack stores are performing better than its premium stores, and the company has shifted toward opening more Rack locations, as a result. There's some concern about diminishing returns on that front, as the recent 0.9% drop in comparable-store sales at physical Nordstrom Rack locations attests. But the retailer has done a good job of using online portals to drive sales, helping the off-price unit produce overall gains in comps.

In addition, Nordstrom has sought cost-cutting measures to improve its bottom line, and that should help it even if the retail downturn lasts for a long time. Given Nordstrom's commitment to treating customers well, if any retailer can withstand the inexorable trend toward pure e-commerce retail specialists that lack a brick-and-mortar presence, it's Nordstrom.