Tropical Wave/Disturbance numbering
Posted: Wed Jun 23, 2010 3:05 pm
Every year or so I use the search engines on the net to try and find the answer to this question. Never found a thing. But I know it exists, evidenced by many news articles referring to "Tropical Wave Number x" or "Tropical Disturbance x".
See article yesterday at http://www.yucatannoticias.com/en/?p=96
"The federal official said that the tropical wave number 7, located off the coast of Quintana Roo, would cause 5 to 20 mm rainfall on Monday and Tuesday, while on Thursday it is expected to feel the effects of the tropical wave number 8 on this part of the country." Wow, wonder which of the over 20 waves we've had so far they didn't count, to be only up to number 7?
And the most confusing yet, about 92L (I think from Antigua Met Service), which got posted all over the internet via news services, forums, online radio, etc., stated:
"Tropical Disturbance 10 was located about 625 miles east of the Lesser Antilles. Movement continues west-northwest to northwestward at about 15 mph. Showers and thunderstorms within this system are poorly organized and the strong westerly winds at upper levels are expected to remain unfavorable for tropical cyclone formation. There is a ten percent chance of this system becoming a tropical cyclone during the next 48 hours."
This information on Disturbance 10 was updated a few days in a row, and mass-distributed by email. We expect the same will happen for each and every unorganized something that is being watched.
So what was Disturbance 1 through 9? And why, when the World Meteorological Organization has designated the National Hurricane Center as the forecast agency for the Atlantic Basin, and there is an accepted protocol of terminology, etc., does another set of numbers show up which have no documentation, and confuse the public? They sure don't mind using word-for-word the Tropical Weather Outlook from NHC. So why add the "Tropical Disturbance 10"? Does anyone know where I can see these numbered "disturbances" or even "twaves" on the net? Or do the numbers mean anything at all, other than something to the person/organization using them?
I've searched the web using "tropical wave number(s)(ing)" - nothing found. Also searched same for "tropical disturbance" and learned that is a valid classification in the SW Indian Ocean, and read hundreds of pages of the same stuff about cyclones, depressions, storms, tropical waves, coriolis effect, etc. the whole bulk of usual stuff and never found ANYTHING about numbering twaves or "tropical disturbances" in the Atlantic (which, by some definitions, is the same thing as twaves). Anybody shed some light on this?
See article yesterday at http://www.yucatannoticias.com/en/?p=96
"The federal official said that the tropical wave number 7, located off the coast of Quintana Roo, would cause 5 to 20 mm rainfall on Monday and Tuesday, while on Thursday it is expected to feel the effects of the tropical wave number 8 on this part of the country." Wow, wonder which of the over 20 waves we've had so far they didn't count, to be only up to number 7?
And the most confusing yet, about 92L (I think from Antigua Met Service), which got posted all over the internet via news services, forums, online radio, etc., stated:
"Tropical Disturbance 10 was located about 625 miles east of the Lesser Antilles. Movement continues west-northwest to northwestward at about 15 mph. Showers and thunderstorms within this system are poorly organized and the strong westerly winds at upper levels are expected to remain unfavorable for tropical cyclone formation. There is a ten percent chance of this system becoming a tropical cyclone during the next 48 hours."
This information on Disturbance 10 was updated a few days in a row, and mass-distributed by email. We expect the same will happen for each and every unorganized something that is being watched.
So what was Disturbance 1 through 9? And why, when the World Meteorological Organization has designated the National Hurricane Center as the forecast agency for the Atlantic Basin, and there is an accepted protocol of terminology, etc., does another set of numbers show up which have no documentation, and confuse the public? They sure don't mind using word-for-word the Tropical Weather Outlook from NHC. So why add the "Tropical Disturbance 10"? Does anyone know where I can see these numbered "disturbances" or even "twaves" on the net? Or do the numbers mean anything at all, other than something to the person/organization using them?
I've searched the web using "tropical wave number(s)(ing)" - nothing found. Also searched same for "tropical disturbance" and learned that is a valid classification in the SW Indian Ocean, and read hundreds of pages of the same stuff about cyclones, depressions, storms, tropical waves, coriolis effect, etc. the whole bulk of usual stuff and never found ANYTHING about numbering twaves or "tropical disturbances" in the Atlantic (which, by some definitions, is the same thing as twaves). Anybody shed some light on this?