02Feb07b

7 February 2002: Cyclone Chris.. Dust storms and Willy-Wiilies

This morning's Melbourne Age carried a photo of a spectacular dust-storm
generated by TC Chris's passage across the desert. The photo showed a
huge haboob/Melbourne-dust-storm style wall of dust, almost certainly
associated with a cold air/density current boundary. I have a few
comments:

a) Does anyone in the Perth Office have any further information on this:
was it just a thunderstorm/CB downdraft, or is there something special
happens with landfalling TC's?

b) Did the Perth papers carry it, and more importantly does anyone have a
digital copy of the photo, or know of a source on the web.

C) I have always been interested in the fact that back in the 1920's the
Bureau used to call West Australian Tropical Cyclones by the name "Willy
Willy"; and that same name has transformed over the following years into
the term (at least in South East Australia) for a dust-devil. It makes
sense, that if the Chris-generated dust-storm as per today's Age is a
common occurrence, the two phenomena (land-falling TC and dust-storm)
could have become one and the same in the minds of our early
language-developers (my predecessors)

cheers

JMcb

Roger Atkinson
My parents and grandparents (and great grandparents, but they're out of the
picture, so to speak), were from WA. (My grandfather used to own Wallal
Downs station but sold it back in the early '60s - good call, that, in the
light of Chris's landfall yesterday. I guess that gives me an interest in
the dust flying around yesterday - at least part of it was no doubt some
ex-family property. But that's not the point. Another coincidence - my Dad
went to uni with Bob Southern. But that's not the point either...)
On previous questioning, they've (my parents and grandparents, of course!
Aren't you paying attention?) said that if the Bureau used to call TCs
willy-willies, that's news to them. They use the term quite commonly, but
know only the meaning the rest of us know, i.e. 08PO, dust devils.
What is the source of your information that WARO used to call a TC a
willywilly?
To my knowledge, the source of 'TC = willy willy' is the General Met book
we all had to study on the Met course. As far as I know it is an error
(i.e. total frogshit). I think my forebears would be offended to think
anyone thought them odd enough to use willy willy in any context other than
that we all use. The expression was very common in WA (especially the
Pilbara), because the phenomenon was very common (i.e. PO), so it's seems
highly unlikely that they'd have confused, or mixed, TCs with POs.

Oh dear, a bit scrambled. It must be Thursday.

Cheers,
Roger A.
Tindal WSO (the land of black and orange striped willywillies - yes, I've
seen a few. true dinks!)

John McBride
I'm in the middle of a meeting so this will be short:
1. Maps put out by the Bureau with tracks of WA cyclones and the label
track of a typical "Willy-Willy" in the
publication" Australian Hurricanes and realted Storms. Commonwealth
Bureau of Met, Bulletin No. 16, by H. A. Hunt, Commonwealth Meteorologist,
Feb 1925

2. Page 78 79 of "Climate and Weather of Australia" , Hunt, Taylor and
Quayle, , Commonwealth Bureau of Meteorology, 1913.

3... many, many other sources in Bureau Documents of that time...

But... I have to get back to my meeting

More later

JMcB

John McBride
Still at the meeting... still busy, so a quick one:

>From the Wall Sheet: TROPICAL CYCLONIC STORMS ON THE NORTH-WEST COAST OF
WESTERN AUSTRALIA _CHARACTERISTICS, SIGNS OF APPROACH etc, published by
the Bureau sometime before 1925.

A few quotes:

"When the barometer shows signs of falling with an easterly wind,
conditions are conducive to the development or approach of willy-willies,
and precautions should be taken accordingly".

"As a precautionary measure during the "willy-willy season, hourly
readings of the barometer and the direction of the wind should be mad by
mariners and entered in the ships log"

And... elsewhere in the publication... (not off the wallchart": 12-18 jan
1899: S.S. tangier encountered willy-willy on 12th off N.W. coast

BUT... its more complicated than that...as sometimes, they say
"hurricanes can generate willy-willies";
and then othertimes, they use hurricane and willy-willy interchangeably.

Roger Atkinson

Hmm, then you have a point. I'd only ever seen them so referred to in our
training school text. Sounds like this Hunt dude may have much to answer
for. Of course it still doesn't tell us where the term originated. Did he
make it up, or was it a meteorologist's expression way back then? From my
own anecdotal evidence (i.e. the sworn affidavits signed in blood and
provided by my forebears) I doubt the usage originated, or has ever been
common, in the west, at least amongst the peasants.
But it's time for my afternoon nap.
Roger

Barry Hanstrum

John

We haven't seen the photo in the local paper here. I'm very keen to have a look at it.

a) Does anyone in the Perth Office have any further information on this:
was it just a thunderstorm/CB downdraft, or is there something special
happens with landfalling TC's?

Without knowing where or when the photograph was taken it's hard to comment. We often see widespread blowing dust in the strong easterly winds prior to coastal crossing but it's usually mixed through the depth of the boundary layer by strong heating, so not at all like the density current appearance of the Melbourne cool change dust storms (eg Feb 7 1983). I'd suggest that the dust storm was associated with one of the storms associated with the outer bands of the cyclone as it
approached the coast. Sometimes these bands can generate very organized convection with severe squall conditions.

b) Did the Perth papers carry it, and more importantly does anyone have a
digital copy of the photo, or know of a source on the web.

Haven't seen it , no digital copy , can someone in Melb contact the Age newspaper to find out its source??.

Interesting thoughts John, we too use the word wiliy willy for dust devils in inland Western Australia. To strengthen the argument about the link between willy willys and the occurrence of dust a large number of the TCs that make it down to the southern parts of the state have rain free quadrants on the very windy side so they typically produce widespread duststorms.

...and as I'm sure you all must have noticed......WA registers yet another Cat 5 cyclone coastal crossing, the 13th severe coastal crossing since 1990!

Baz way out west

Blair Trewin
There's certainly no doubt that 'willy-willy' was used extensively for TCs
in the late 19th/early 20th century. Its local use for this, from the
sources I've seen, seems to have ceased by about the 1920's or 1930's, but
it lives on today in sundry overseas books about Australian weather/climate
that keep perpetuating the archaic terminology that they copied out of
whatever book they used as their source. (The term 'brickfielder' for hot
N/NW winds in the SE Australian cities also gets a guernsey in many such
publications, despite having fallen into disuse many years ago).

Blair