Crude Oil Refinery TexasSpencer Platt/Getty Images
Crude oil is back in a bull market. 
Futures have rallied 22% since the recent bottom on August 2, when they fell below $40. On Thursday, West Texas Intermediate crude futures in New York rose 2.8% to $48.11 per barrel, a six-week high. 
Oil has gained in every session since August 11 as reports of talks towards a production-freeze agreement among OPEC producers were revived. 
Saudi Arabia's Energy Minister Khalid al-Falih said last Thursday that the country was ready to take "any possible action" to rebalance the oil market, which is currently oversupplied. 
Additionally, data from the Energy Information Administration on Wednesday showed that US crude inventories unexpectedly fell by 2.5 million barrels last week, more than forecasters had estimated, and following three straight weeks of builds. 
But the rally is still under threat. Last week, the International Energy Agency cut its forecast for global oil demand next year. 
And, Reuters reported that Saudi Arabia could in August raise its output to new records of between 10.8 and 10.9 million barrels per day. 
Here's a chart showing the rally in WTI:Screen_Shot_2016 08 18_at_1_07_28_PMInvesting.com