Tuesday, October 19, 2010

The Weather in North Carolina


This is Cruise to the Bahamas 2.0. White Pepper is determined to learn from past experience and correct the mistakes of the first voyage. One thing that bamboozled us on the first trip was the weather. It is hard to emphasize how important the weather is to the comfort and safety of the small cruiser, esp. one that makes as few concessions to comfort as a C&C 41. Lack of accurate weather information or fear of adverse weather kept us hunkered down for too many days in 2008.

What is little appreciated by the sailing community (and by me until recently) is that there has been a revolution in weather forecasting. It is called gridded binary data or GRIB. Four times a day super computers in the USA and Europe crank out modeled forecasts processed from mountains of data gathered from around the world. This world wide aspect eliminates any boundary value problems that so bother the differential equations of fluid dynamics. The forecast is remarkably accurate for 24 hours. Seventy two hours is good, but the 5 and 7 day forecast is as awful as it ever was. You can witness this modern miracle for yourself on Sailflow.com, and you can be blown away with the graphics on mySailflow all for free. NOAA is part of the game as well. Now NOAA.gov will tailor a micro forecast for an area smaller than a zip code. And it is remarkably accurate in the near term. Raw GRIB data is freely available in the public domain. A GRIB reader program is required to display the data on the computer screen.

I purchased Chris Parker's recent book about weather and the important part was how to use the GRIB data. He states that GRIB is as revolutionary to weather forecasting as GPS was navigation! If you are interested you can find Chris' new book at Landfall.com but not Amazon.com.

The great problem of the annual migration south to the Bahamas is the weather. Start too soon and you have to dodge hurricanes. Start too late and cold fronts become unbearable. The traditional start of the migration is after the Annapolis boat show which was our signal to take off.

On this trip we have regular access to the internet via a Verizon wireless "hot spot" and complete access to weather. We got nailed in the Dismal Swamp with torrential rains but knew that the wind would not be a problem until later. We tied up at Elizabeth City and watched for two days as the wind whistled over head. The two days were not wasted as I did chores on the boat. Jan attended the wonderful Sat am farmers market in Elizabeth City. The picture is a still life of fall colors from that market. Five miles down the Pasquatank River from Elizabeth City is Albemarle Sound. This is a shallow body of water about 10 n. miles wide, notorious for a wicked chop. It is not to crossed except in settled weather. This came on the 17th, my birthday. After the Albemarle comes the Alligator River, which is short but windy as it funnels wind north or south. The river must be viciously cold in norther. We just motored down it in gentle warm breezes. After a quiet night in Belhaven NC there was more of the same for the next day on the Pungo and Pamlico Rivers.

Currently there we are anchored just off Oriental, NC. The anchorage is marginal, but I am not worried as the forecast is for a quiet night. There is a weak front off to the north that will work through tomorrow. It should be quiet for the motor to Morehead City. Friday or Saturday will bring light northerly flow perfect for the trip offshore to Wrightsville Beach or points south. I could go on, but I hope the gentle reader gets the picture of using the internet and e-mail to sail in comfort and safety.

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