A huge mega-storm hurtling off the Pacific threatens “life-threatening floods” while “feet of snow” pile up in a “rare” weather event. California is in the firing line for “the largest storm of the season” this week as the National Weather Service (NOAA) issues a raft of danger-to-life alerts. Potentially “unprecedented floods” will be driven by torrential downpours whipped through the region by fierce gales. Coastal regions are at greatest risk from severe weather which meteorologists warn should be “taken seriously”, as flood watches remained in place for nearly 40million people. An atmosphe…