On Sunday, we experienced a rare “blowout tide,” an exceptionally low tide. “Blowout tide” is a colloquial term for what oceanographers call a “wind setdown” when water is blown away from shore. Along the Hudson River, these occur when sustained, strong north-northwest winds drive the ocean tide offshore from New York Harbor, which in turn draws down the Hudson River. It drains tidemarshes and inshore shallows, exposing areas of the river bottom that are normally under water. With the blowout, Sunday’s ebb tide was over two-feet lower than normal. Locally, it offered a glimpse of the mudflats north and south of the Lighthouse. The blowout revealed the shoals for which the Lighthouse stands as a warning to prevent ships running aground. It also exposed the wreck of the Saugerties, an old steamliner scuttled in the flats in the early 1900s.