This is going to sound cynical but I witnessed the exact same thing with support for healthcare reform after SiCKO was released and with the climate crisis after An Inconvenient Truth.
In the wake of Hurricane Sandy, you can expect a surge in public support for climate legislation -- new regulations on CO2 emissions, calls for more renewable energy, and so forth. But as soon as someone -- hopefully President Obama -- tries to pass anything, public support will crash back to pre-Sandy levels.
The sad fact is that most Americans would rather endure the potential (or reality) for devastation rather than buy hybrid cars and eat less factory beef for dinner. If record heat, freakish weather and monster storms, say nothing of the massive BP oil spill in the Gulf, won't convince Americans to demand action and stick with it, I don't know what will.