Hurricane Teddy will pass well east of Cape Cod over the next 24 to 36 hours keeping the core of its truly nasty weather out over the ocean. The storm, located southeast of Bermuda Monday morning, will move northward over the next two days, paralleling the east coast of the United States as it heads toward Nova Scotia. While the worst of Teddy’s weather will undoubtedly remain offshore, we will feel some impacts here on the Cape.
As Teddy moves into the Northwest Atlantic it will transition from a purely tropical system to more of a post-tropical cyclone. As part of that evolution, its wind and pressure fields will expand markedly. All the while, strong high pressure will remain anchored near New England, creating a large pressure gradient over the Gulf of Maine and coastal waters of New England. The combination of this tight pressure gradient and Teddy’s expanding wind field will yield a period of strong northerly winds here on the Cape Tuesday and Tuesday night.
Model guidance is in good agreement that winds aloft – at about 925 mb or 2000′ above ground – will peak near 50 knots Tuesday afternoon and evening over the Outer Cape and closer to 40 to 45 knots on the Mid and Upper Cape. Simultaneously, guidance shows a temperature profile between the surface and this same height in the atmosphere that is very conducive to “mixing” – meaning these stronger winds aloft can be transported toward the surface.
The end result – expect a very windy day on Tuesday with frequent wind gusts to 40 mph around the area and likely some gusts in excess of 50 mph on the Outer Cape. With fully leafed trees, that kind of wind will probably yield some pockets of tree/limb damage and may bring some scattered power disruptions to the region.