The setting is clearly during cold winter weather in Houston (visible breath from the characters), and since it was set shortly after the 2011 Super Bowl (depicted the prior week in Roundup (2011)), this sets the time period as around the middle of February. In the flashback from 4 months earlier circa September 2010, it is still very cold outside as evidenced by visible breath from the characters and the exhaust from the vehicles when the officer pulls the car over. This reveals the flashback was filmed at the same time. The coldest it got in Houston in September 2010 was 61 degrees, while a week after the 2011 Super Bowl it was 27 degrees.