And Cushing isn't the only location to watch.
Wood MacKenzie's York noted that the Gulf Coast will become increasingly important, especially if record inventories continue.
"It's a question whether Cushing plus the U.S. Gulf Coast capacity could fill up, and that would ... set up a very serious price dynamic, some serious volatility introduced to the market," he said.
Crude stored along the U.S. Gulf Coast has also increased, though not nearly as fast as Cushing has, since storage along the coast is more spread out, less interconnected and considered riskier.
Nonetheless, as prized tank real estate in Cushing is snatched up, more crude is flowing south, helping contribute to the 5-million-plus-barrel build reported by the U.S. Energy Information Administration this week.
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It's highly unlikely that the Gulf region will fill up, but oil data over the next several weeks will be key. If oil continues to be stockpiled, and storage does actually reach full operating capacity in Cushing, then more oil will be forced onto the market, possibly pushing WTI dramatically lower.
If that happens, more wells will end up capped, and the United States' current 9.3 million-barrel-per-day production boom will finally begin to decline. Even so, it would still take time for the crude socked away in storage tanks to unwind, potentially masking a budding supply crunch.
Then the entire cycle would begin again.
"It generally plays out the same way," said Triad's McDonald, a three-decade industry veteran. "The only issue is the length of the cycle, and that'll be a function of supply and demand."
However long that process takes, in the meantime, just outside the geographical limits of the tiny town of Cushing, some $2.5 billion worth of black gold is sitting in tanks, awaiting delivery and drawing the attention of the entire industry.