“Can somebody kindly explain why this is happening?”
Unfortunately, that’s something no one can really do. Gasoline prices are very difficult to explain or predict, even more so than other commodities. There are so many market forces acting at the same time that at any time you can come up with multiple theories both for and against the current trend.
Situation in Tripoli brings prices up vs. down depending on whether your theory is unstable now vs. expecting stability soon. Hurricane Irene brings prices up vs. down because of stockpiling and emergency services mobilizing vs. potential demand destruction in the areas hit. There are probably dozens of other theories you could come up with at any time.