Unpredictable weather in New England is, well, predictable. Jay Peak Resort in Northern Vermont is making it more tolerable when it interferes with vacation plans. The resort is unveiling the Pump House Water Park to its collection of new indoor amenities that include 2009’s Tram House Lodge and Spa and 2010’s NHL-sized hockey rink. The idea, as the song sort of goes, is “when the weather outside gets too frightful, the fun inside is just delightful.” The new $27 million waterpark features a retractable roof and an AquaLoop slide that drops riders into a 60-foot freefall before sending them into an upside loop at speeds of 45 mph. It also is home to the largest indoor action river in North America and the Double Barrel – a twin FlowRider standing wave for “surfing Vermont.” The Pump House is part of the largest current construction project in the state that also includes the Hotel Jay and Conference Center.