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Hurricane activity in the Atlantic linked to QBO phase. How is the theory holding in 2013?

CURRENT HURRICANES in the ATLANTIC
current atlantic hurricanes

source
http://www.wunderground.com/hurricane/?index_region=at

CAVIN RAWLINS is a guest poster and blogger on WUNDERGROUND which an excellent weather analysis site
Cavin uses the avatar name ‘weather456’
http://www.wunderground.com/blog/Weather456/archive.html?year=2008&month=03

CAVIN in one of his posts identifies the link between Atlantic hurricanes and the phase of the QBO
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( QBO.. wind direction at the ~ 10 hPa layer)

A substantial tutorial about the QBO from this link

    The Quasi-Biennial zonal wind Oscillation

http://www.ugamp.nerc.ac.uk/hot/ajh/qbo.htm

Here l have assembled some QBO ammunition
https://weathercycles.wordpress.com/2013/08/10/qbo-time-series/

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From CAVIN’s post
“During the QBO, Atlantic tropical cyclones are more frequent when 30 mb winds are westerly and increasing, rather than easterly and increasing. There have been 44% more hurricanes and 74% more hurricane days during the west as opposed to east phase of the QBO.
Atlantic tropical cyclone activity is inhibited during easterly phases of the QBO due to enhanced lower stratospheric wind ventilation and increased upper-troposphere-lower stratosphere wind shear.”
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So…
In what QBO phase are we currently in ..August 2013
The QBO changed phase into the WESTERLY /positive anomaly in March 2013 and has been increasing . As of august 2013 we are recording an anomaly of Positive 14.27
Weare in a westerly phase of the QBO and has been increasing since March 2013
http://www.esrl.noaa.gov/psd/data/correlation/qbo.data

I think the Atlantic has been quiet as of August 2013.
However peak cyclone season is due in September.
… with the Westerly QBO phase favouring Atlantic hurricane activity.??

It should be remembered that this is a statistical probability
44% more hurricanes in the westerly phase..

Lets see how the Atlantic hurricane season matches these predictions at the end of the season.

Will revisit this say in November when the data records for the 2013 season become available

So far the westerly QBO increasing = Above the mean hurricanes does not appear to be valid so far in 2013

Lets see…

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2 comments on “Hurricane activity in the Atlantic linked to QBO phase. How is the theory holding in 2013?

  1. Hurricane season still relatively weak.
    ACCUWEATHER have a very detailed discussion on the lack of Atlantic hurricanes
    http://www.accuweather.com/en/weather-news/2013-in-running-for-latest-atl/17382707

    some snippets
    The 2013 season has a chance at producing no hurricanes through the middle of September, which would rival two records. The 2002 late season September 11th ‘Gustuv’ and the 1941 late season hurricane of September 16th.However finally 4 late hurricanes ultimately emerged

    While the 2013 season thus far has delivered seven tropical storms, it has not delivered any hurricanes as of Sept. 5

    According to Hurricane Expert Dan Kottlowski, “Even though dry air has backed off a little in recent days, strong westerly winds aloft continue to interrupt tropical development for almost every budding system.”.

    map of steering winds atlantic

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