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CanisLupusArctos · 07-07-2008, 01:18 PM

On May 16 I read this post from Seablogger:

http://www.seablogger.com/?p=10782

Look at his prediction, and compare it to what is happening right now.

Sea surface temperatures affect overall weather patterns which are the usual driving force behind the tracks of hurricanes (and other weather systems.) We know that El Nino and La Nina -- warming and cooling of the equatorial Pacific waters -- alter weather patterns across North America.

We also know that hurricanes in the Atlantic are often subject to the weather systems around them. A hurricane may be headed for the east coast when suddenly high pressure builds on the coast and deflects it out to sea. Sometimes high pressure builds to the north of a hurricane where Bertha is, and keeps it from curving that way. There are many more examples.

Given the above, it's possible for Pacific sea surface temperatures to affect the tracks of Atlantic hurricanes.

I don't think hurricanes follow the warm water, or else they'd all be stronger and not many would stray into colder waters and weaken like so many do.

A funky fact to remember is that hurricanes also require cold air. They're not just heat machines -- like anything else that goes zip, boom, or pop, hurricanes are a reaction between different entities.

They start as a cluster of strong thunderstorms, which require cold air aloft in order to become severe. Many of those thunderstorms form over Africa and move off the coast toward Cape Verde where they disrupt the normal ocean wind pattern and start a new circulation that grows into a hurricane. There have been stories of ship captains sailing under the hurricane formation process and reporting frozen locusts falling on the decks along with the heavy rain. The locusts were most likely sucked into the thunderstorms' updrafts when they were still over Africa. The outermost wisps of the storm (which cover the top of it) are cirrus (and variations of cirrus) which are made of ice crystals.

The role of water temp along the East Coast does play a role in the strength of any hurricane that comes up this way. If the existing weather pattern favors a track up the east coast, the storm will most likely take it. If the storm finds warm water along that route, it will maintain its strength.

Usually hurricanes lose a lot of strength on their trip up the east coast because the waters cool drastically from Florida to Cape Cod. The Hurricane of 1938 had speed on its side. It made the northbound trip with such speed that it didn't have much time to lose strength. Also, a hurricane's forward speed adds to the wind speed on one side of the storm (while subtracting from the other side.)

Visual: The hurricane spins counterclockwise, like a pinwheel. When you put the center of the pinwheel right on the coast (landfall) the wind on one side of it will be coming ashore, while the wind on the other side of the pinwheel will be blowing from the shore to the sea.

If the whole system has maximum sustained winds of 100 mph and a forward speed of 30 mph, the winds coming ashore will be 130 mph while the winds on the other side of the eye (blowing from beach to sea) will be 70 mph.

The Hurricane of 1938 had an incredible forward speed. In addition to beefing up the storm's forward-blowing winds, it also gave the storm a greater element of surprise than it otherwise would've had. The stories I've read are incredible; people said the day started off normal and very quickly grew into a hurricane. They already had little time to prepare because the NWS had no sattelites back then. There were ship reports and that was about it.

Today we are just as ill-prepared in New England because it's been so long since we got a huge hurricane. A few old people remember, and most young people haven't listened to them. Although we have satellites and radar and computer-guided forecasting, people will likely look at those images and say, "It won't hit us because it never does." Psychology, not meteorology, will cause the most damage and death.

There is now a lot more in such a hurricane's path for it to destroy, so the next one will likely be much more costly. Today, too many people in New England have grown up without a good hurricane-lashing and have built their houses of cards.

07-07-2008, 01:18 PM	#11
CanisLupusArctos Senior Member Join Date: Jan 2007 Location: Center Harbor Posts: 1,049 Thanks: 15 Thanked 472 Times in 107 Posts	On May 16 I read this post from Seablogger: http://www.seablogger.com/?p=10782 Look at his prediction, and compare it to what is happening right now. Sea surface temperatures affect overall weather patterns which are the usual driving force behind the tracks of hurricanes (and other weather systems.) We know that El Nino and La Nina -- warming and cooling of the equatorial Pacific waters -- alter weather patterns across North America. We also know that hurricanes in the Atlantic are often subject to the weather systems around them. A hurricane may be headed for the east coast when suddenly high pressure builds on the coast and deflects it out to sea. Sometimes high pressure builds to the north of a hurricane where Bertha is, and keeps it from curving that way. There are many more examples. Given the above, it's possible for Pacific sea surface temperatures to affect the tracks of Atlantic hurricanes. I don't think hurricanes follow the warm water, or else they'd all be stronger and not many would stray into colder waters and weaken like so many do. A funky fact to remember is that hurricanes also require cold air. They're not just heat machines -- like anything else that goes zip, boom, or pop, hurricanes are a reaction between different entities. They start as a cluster of strong thunderstorms, which require cold air aloft in order to become severe. Many of those thunderstorms form over Africa and move off the coast toward Cape Verde where they disrupt the normal ocean wind pattern and start a new circulation that grows into a hurricane. There have been stories of ship captains sailing under the hurricane formation process and reporting frozen locusts falling on the decks along with the heavy rain. The locusts were most likely sucked into the thunderstorms' updrafts when they were still over Africa. The outermost wisps of the storm (which cover the top of it) are cirrus (and variations of cirrus) which are made of ice crystals. The role of water temp along the East Coast does play a role in the strength of any hurricane that comes up this way. If the existing weather pattern favors a track up the east coast, the storm will most likely take it. If the storm finds warm water along that route, it will maintain its strength. Usually hurricanes lose a lot of strength on their trip up the east coast because the waters cool drastically from Florida to Cape Cod. The Hurricane of 1938 had speed on its side. It made the northbound trip with such speed that it didn't have much time to lose strength. Also, a hurricane's forward speed adds to the wind speed on one side of the storm (while subtracting from the other side.) Visual: The hurricane spins counterclockwise, like a pinwheel. When you put the center of the pinwheel right on the coast (landfall) the wind on one side of it will be coming ashore, while the wind on the other side of the pinwheel will be blowing from the shore to the sea. If the whole system has maximum sustained winds of 100 mph and a forward speed of 30 mph, the winds coming ashore will be 130 mph while the winds on the other side of the eye (blowing from beach to sea) will be 70 mph. The Hurricane of 1938 had an incredible forward speed. In addition to beefing up the storm's forward-blowing winds, it also gave the storm a greater element of surprise than it otherwise would've had. The stories I've read are incredible; people said the day started off normal and very quickly grew into a hurricane. They already had little time to prepare because the NWS had no sattelites back then. There were ship reports and that was about it. Today we are just as ill-prepared in New England because it's been so long since we got a huge hurricane. A few old people remember, and most young people haven't listened to them. Although we have satellites and radar and computer-guided forecasting, people will likely look at those images and say, "It won't hit us because it never does." Psychology, not meteorology, will cause the most damage and death. There is now a lot more in such a hurricane's path for it to destroy, so the next one will likely be much more costly. Today, too many people in New England have grown up without a good hurricane-lashing and have built their houses of cards.