mninjapan : You are right, normally the front month should be in contango. It actually is in cantango even now if you include the spot price, but normally the front month should each month transition from backwardation to contango to the 2nd month. There is definitely an anomaly in the front 2 months, but it seems to have been fading since it showed up. Perhaps it will eventually go back back into contango.
The front month contango is traditionally caused by pension funds and Oil index funds that are always long the front month as part of an indexing strategy and keep the front month above spot. After they roll (5th to 9th trading day of the month) the front month should also go into contango relative to the 2nd month. Normally speculators will spread the front month contango across 2-3 months. This is also normally the source of front month contango in Brent, though the contango extending 6 months is an anomaly, perhaps due to the short position unwinding.
However lately for CL the hedging needs of US fracking companies has completely overwhelmed the speculators and may now even have overwhelmed the pension funds and Oil index funds, which would put all months into backwardation. In that case however the front month backwardation would NOT exceed the other months, since it would then be cheaper for US fracking companies to hedge using the back months than the front month, eventually equalizing the front month backwardation. Therefore I can't explain the front month backwardation being steeper than the next few months in CL.