![\"Bill](\"https:\/\/setsail.com\/wp-content\/uploads\/2009\/08\/billtransition1.jpg\")
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We are in the habit of watching the GFS weather model via Sailmail’s Saildocs offerings. This morning Hurricane Bill popped up. We’re not interested in the tropical phase but in seeing if it is forecast to transition to extra tropical structure.<\/p>\n
The chart above is for 96 hours from now or 000Z on the 24th. Note that Nova Scotia and Newfoundland are in the path even though they are surrounded with cold water. No doubt those of you along the Eastern Seaboard of the U.S will be watching Bill closely.<\/p>\n
The question we are concerned with here, about transition of the structure of the storm, will be based on what is going on at the 500mb and higher levels.<\/p>\n
Now look at 120 hours from now.<\/p>\n
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![\"Bill](\"https:\/\/setsail.com\/wp-content\/uploads\/2009\/08\/billtransition002.jpg\")
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Hurricane Bill is now a full fledged Norwegian type of depression. Wind strengths are down in this forecast from what would be found with hurricane structure, but the storm covers a much wider area than the tropical phase of the weather, and so is more difficult to maneuver away from.<\/p>\n
![\"Bill](\"https:\/\/setsail.com\/wp-content\/uploads\/2009\/08\/billtransition003.jpg\")
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The forecast for 168 hours from last night. This is a huge storm and will create enormous waves. It also needs to be watched for a dynamic fetch scenario, where the storm system accelerates and moves at the same speed as the waves it is propagating. This would create truly awesome seas.<\/p>\n
Even though we are in harbor in Scotland, 3000 miles away from Hurricane Bill’s present location, we are going to keep a close eye on this system. It could easily impact us five to seven days from now.<\/p>\n
Dynamic fetch and tropical to extra tropical transitions are discussed in detail in our Mariner’s Weather Handbook<\/em>.<\/p>\n","protected":false},"excerpt":{"rendered":"