Hurricane Watches have been hoisted across New England and, depending on the exact strength at landfall, New England may be staring down the barrel of the first direct hurricane strike to our coast since Hurricane Bob in 1991. We’ve seen plenty of tropical storms, decaying hurricanes and nor’easters, but a storm of this magnitude, making a direct strike as a hurricane, hasn’t come calling in 30 years. So, it’s all eyes on Henri as the Tropical Storm is predicted to strengthen to a hurricane strength as it drifts from a position south of Bermuda to a location squarely over the warm waters of the Gulf Stream – the warm current of ocean water off the Eastern Seaboard that favor storm strengthening. If the storm follows the latest official track and intensity from the National Hurricane Center, it will landfall along the South Coast of New England as either a strong tropical storm or minimal hurricane, with widespread wind damage and power outages, flooding rain, coastal flooding due to high tide and storm surge and significant loss of property due to storm surge along New England’s South Coast can be expected. Conditions are expected to deteriorate rapidly Sunday morning – after two relatively benign days Friday and Saturday. With lots of clouds and an occasional shower Friday, humidity continues but will build even more Saturday as a light southeast wind begins, carrying truly tropical air into New England ahead of the strengthening storm to our south. As dew point temperatures rise and the moisture content of the air increases, sunshine will give way to building clouds and scattered afternoon tropical showers – still innocent enough. Clouds increase Saturday night and problems compound Sunday as the southeast wind strengthens across Southern New England early in the morning. With rip currents gradually building at New England beaches over the weekend, beachgoers will need to exercise caution, particularly with kids. Henri will waste no time Sunday, with bands of rain and gusty wind arriving to Southern New England by early to mid-morning and conditions will rapidly deteriorate over the morning to midday. By Sunday afternoon, rounds of damaging southeast wind will be impacting most of Eastern MA and RI, with a northerly wind on the west side of the storm track, currently predicted to be into Western RI but with a cone of probability that includes possible tracks anywhere into the South Coast. Gusts may exceed 90 mph at exposed coastal locales, and will top 50 mph for many on the east side of the storm track. For comparison, power outages from Hurricane Bob lasted more than a week for some, so all residents of Southern New England, southeast NH and coastal ME should check generators and start making preparations for extended outage potential. Storm surge will be worst near where the eye of the storm comes ashore, so all areas along New England’s South Coast should make preparations for areas of inundation and damaging, surging waves that will result in evacuations for some vulnerable spots. The Eastern coast of New England is also subject to coastal flooding owing to the strong onshore wind, and those who own boats should follow your marina or Harbormaster’s suggestions, as each locale will respond a bit differently based on the slope of the coast and direction of the wind. Rainfall of at least three to five inches with locally in excess of half a foot will result in pockets of flash flooding Sunday afternoon and night, with both small and mainstem rivers rising Sunday night into Monday and river flooding a concern as the rain runs off into the river basins. In a situation like this, residents both at the coast and inland should follow the advice of local emergency managers, who reference well-studied research when suggesting or ordering evacuations. At this point, we are hoping for a weaker storm or an altered storm track, but the window for that is closing and New England must make preparations for the most likely outcome, described here. The storm will weaken with gusty rain lingering Monday but drift east to the Gulf of Maine and sun returns Tuesday.