Hurricane Watch

Friday 3rd September 2010, day 686, 12,013 miles. 40° 57’.37N 073° 05’.20W. Port Jefferson, Long Island, NY

We’ve learnt a lot about hurricanes in the past week, as Earl has tracked relentlessly up the coast towards us.

Firstly, how very good the weather forecasters have got. On the US’s excellent National Oceanic and Atmospheric Administration website, http://www.nhc.noaa.gov/ hurricanes’ lives are tracked and predicted, from the incipient tropical wave forming vaguely off the west coast of Africa, somewhere near the Cape Verdes, to the tropical storm as the wave turns into a depression, forms, solidifies and starts to spin, to the forecast track of the final hurricane.

The second thing is how much time we have to prepare. Earl has been around for over a week, forecast to turn into a hurricane back last Wednesday, when it was still out in the Atlantic, several hundred miles east of the Caribbean islands. The forecasters produce a “cone”, showing not only the likely track, but the widening area of places where the hurricane could reasonably go, updated several times a day. Since last Saturday, when its path seemed likely to cross ours, we have been monitoring it daily, and getting advice from all our local friends about the best place to be if it did coincide with us.

Then there’s the combination of geography and meteorology which means that the eastern seaboard of the US tends to suffer less from a hurricane going by than the South. Hurricanes are an extreme form of a standard depression, with the wind blowing anti-clockwise around the centre. The winds blow around the centre at the same speed, wherever they are on its surface, but the hurricane itself is also moving, affecting the actual wind speeds generated. Earl is moving north east at the rate of about 20 miles an hour. In its north-western quadrant the wind is blowing from the north east (it goes anti-clockwise about the centre, remember), so the hurricane’s own velocity reduces the effective wind by 20 mph. In the south-eastern quadrant, on the other hand, the wind is blowing to the north east, increasing the effective wind.

Earl’s own wind right now is about 70 mph, giving a wind of 90 mph on the south east of its passage, but a more manageable 50 on its west. Hurricanes normally pass along the east coast, a bit offshore, so, here, the coast gets the lesser wind.

And in practice, for us? We spent the last few days with friends on the eastern end of Long Island. Wonderful people, happy and funny and easy and a pleasure to spend time with. We varnished our floorboards on their deck (they are yachties too, so quite understand), swam in their bay, drove round the ultra-exclusive resort of East Hampton marvelling at the size of the gated estates, laughed a lot, and fretted about Earl in between times. Brenda lent me the use of her bath, and I spent a blissful hour up to my neck in bubbles, reading Margaret Atwood’s The Blind Assassin.

The predictions as of yesterday morning were for Earl to graze the tip of Long Island, so regretfully we sailed away, to the western end of Long Island Sound, where the forecast today is for nothing more than 15 -20 knots of wind. The people we are worried about are our friends, who will get worse weather than us.

And that’s the final thing we’ve learnt about hurricanes. It’s much better to be on a boat, mobile, than not to have the ability to move your home out of the way.