Looking at the chart correlation going back to 2006, Garner found that the relationship between crude and the euro gets stronger around tops and bottoms. Lately, they have been trading together, which suggested to her that there could be a bottom nearing for both.
Garner also found that historically the euro tends to lead the way in trend reversals. So, when it approaches a top or a bottom, the euro makes the first move and then oil will follow suit after excessive volatility.
Despite the Fed's recent move to take rates higher, which could strengthen the dollar, Garner thinks the rate hike could already be baked in. She believes the recent action could be a hint that there will be a significant rebound in the euro, followed by crude.
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Garner also noticed looking at the weekly chart of crude that the Relative Strength Index, which is an important momentum indicator, has been trending higher even though the price of crude has declined. This could signal that oil could soon begin to rally, perhaps before the end of the year.
Oil has also been making a wedge formation going back to January, and, based on that pattern, Garner thinks the floor of support should be $33.80. If oil can break above the top of the wedge pattern at $40, then she thinks it could run up to the $60s before it runs into resistance.
"I don't know if her predictions will come true, but if Garner is right, that would be very good news for this crazy-town stock market," Cramer said.