As most Americans have already noticed, it's been a hot summer. In fact, the country is on pace for the hottest year in recorded history after the mild winter earlier, and the abnormal weather is having effects on markets far and wide. Recently, the drought in the Midwest has sent commodity prices for corn and other crops soaring, but perhaps the most surprising change has been the recovery in natural gas. Gas prices had been plummeting for the last few years because of the supply boom caused by hydraulic fracturing, but the high demand for air conditioning and the natural gas to power the country's cooling needs has eased worries of a supply glut. Natural gas is now at a 2012 high of $3.06/MMBtu, and United States Natural Gas (NYSE: UNG), the ETF tracking natural gas prices, has gone up more than 40% since mid-June -- though some analysts see a limited upside from this point as continued record heat would disincentivize further switching from coal to gas-powered plants.

Let's take a look at some other gas stocks that are winning on the recent heat.

Gas storage
One of the biggest fears surrounding natural gas had been that storage capacity would run out before the winter extraction months hit, since last year's mild winter left abnormally high supplies of gas remaining in storage facilities. Whereas gas levels normally deplete to around 1,600 bcf by the end of the winter, this year only saw them decline to 2,400 bcf. Gas levels have reached close to 4,000 bcf in recent years, and total working capacity is just around 4,500 bcf.

Niska Gas Storage (NYSE: NKA) has climbed about 30% in the last month as it now appears that storage capacity will not run out this year. This helps keep the price of gas up, as excess supply would have caused a fire sale for natural gas since there would be no ability to store it. Higher prices also benefit Niska, which does its own proprietary trading and benefits from elevated prices and volatility in the gas market. With estimates of just $0.06 per share this quarter, analysts seem to be giving Niska a relatively low bar to jump over. The company reports earnings next week on Aug. 2.

PAA Natural Gas Storage (NYSE: PNG), meanwhile, has climbed about 4% in the same period of time. Its recovery hasn't been as strong as Niska's, probably because Niska's stock tanked last year after the company suspended its subordinated dividend and took a $250 million goodwill impairment charge. Both companies offer exceptional dividend yields as well, with Niska paying 11.2% and PAA 7.8%.

Low-cost producers
The cost to get natural gas out of the ground and to market varies widely depending on a number of factors. Like Niska, Ultra Petroleum (NYSE: UPL) fell sharply as commodity prices crumbled, but the stock has made a comeback in the last month, up about 25% since mid-June. At a P/E of just 7.2, the company looks cheap based on past earnings. Of course, continued strength will require natural gas prices to remain elevated. Long-term trends seem to indicate more consumption as utilities switch to natural gas and it becomes more commonly used as a fuel.

Similarly, Southwestern Energy (NYSE: SWN) has jumped in the past few weeks, climbing about 25%. The argument for Southwestern is much the same as for Ultra, though Southwestern is not as cheap based on historical measures. As a low-cost producer, it is most likely to benefit from the modest appreciation in gas prices while its competitors suffer. Both companies will report earnings next week. Analysts expect an EPS of just $0.25 from Southwestern and $0.33 for Ultra.

Foolish takeaway
Despite the extreme volatility and uncertainty surrounding natural gas, our CAPS community is bullish on all four of these stocks, giving five stars (out of five) to all except Southwestern, which merits four stars. According to the members, the main argument for gas storage stocks seems to be that facilities will grow more necessary as natural gas usage becomes more prevalent and production increases. Unsurprisingly, they see the low-cost producers as the most likely to benefit from the modest recovery we've seen over the past month. No one knows for sure where natural gas is going, but these stocks look like some of the best plays in the sector. Look for earnings reports coming up to see how they dealt with rock-bottom prices in the second quarter.

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