On Wednesday, 18 September 2013 16:47:48 UTC+1, Dick wrote:
On Wednesday, September 18, 2013 2:17:13 PM UTC+1, exmetman wrote:

As you can see from the results, the chart shows a peak in mid-January that erratically diminishes to around 50% at the beginning of June. This remains fairly flat till the second week of August when it begins to steadily increase up until the beginning of December when it flattens of a little. There is no real sign of any surge in the Gale index at the exact date of either the spring or autumn equinoxes, but there are minor peaks at around the 1st of March, and in the first week of October, that come closest to the dates of the equinoxes.

So no real sign of any equinoctial gales in either spring or autumn, just a steady decrease in the daily frequency of gales in spring, and a steady increase in autumn.

CEP Brookes, writing in his 'English Climate' 1954, says of the Autumn equinoctial gales:

'There is often a stormy period in mid-Sept, with a peak date of the 20th.. The belief that a violent storm may be expected about the Autumn Equinox goes back at least to Shakespeare's time (Macbeth) and though its origin is not definitely known, it is not improbable that it was brought back by sailors to America, for it happens that West Indian hurricanes are most frequent around that date'

However, Brookes regarded the Spring Equinoctial gales as a complete myth..

The median line is more like that in times past a strong gale year would be considered the Equinoctial. Doesn't Brooks or Lamb remark about the solstices too. Winter's in the early 1990 for example?

I read something to that effect on the FAQs recently.

It's quite probable that philosophers of Shakespeare's day may have provided a loose background for a lot of his characters such as for example: Prospero (just going by the choice of his name.)

In more recent times the "equinoctials" have been displaced by super-quakes and recently high VEI eruptions. I don't suppose anyone has made an in depth comparison before dismissing such an idea.

They'd as like to make forecasts by looking through a glass. (Like I did a few years ago, quite successfully IIRC. (Which I do!))

Back to the point: The Intertropical Convergence Zone statistically moves with the tropical storm season. That season as we have seen recently can be as erratic as hell.

The fact the Atlantic season actually starts with the tornado season in the USA seems astonishingly unremarked. However I am pretty sure that the Australian Bureau of Meteorology will provide for us all before it is too late. Of course by then it WILL be too late. (Too late but interesting.)

You've been warned :~)