Author Topic: 29th March 2008 and 23rd March 1997 - A comparison  (Read 3519 times)

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Offline Jimmy Deguara

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29th March 2008 and 23rd March 1997 - A comparison
« on: 31 March 2008, 09:56:39 AM »
I just remembered this morning something I was thinking about yesterday whilst watching the storm - actually even before watching the storm. This should have sent alarm bells ringing to at least check the models (Michael Bath may wish to post some of the old data as a comaprison linking this event with the old event).

On the 23rd March 1997 (yes I know there is no comparison in terms of severity), the conditions and setup was similar and at a similar time of the year yesterday being the 29th March! On this day, there were large cumulonimbus off the coast persistent throughout the day. During the early afternoon, storms developed near Sydney and then dissipated. Later in the day, another storm developed over the Sydney region - probably supercellular. More storms also developed over the Illawarra with a funnel cloud reported. Given the deep inflow that seemed to be experienced in the storm yesterday, it was a shame the instability was not there or was it the lack of surface heating. The winds were northerly and there was I think a change encroaching the Sydney area. I would not be surprised if both events have a boundary of sorts and a triple point in progress where the storms developed and became mature.

Here are the links to the pictures - check out Michael's ones in particular - I was busy that afternoon to my disgust! Michael's pictures cover the whole day well as well as the evening.

http://www.australiasevereweather.com/photography/photos/1997/jd19970323.html

http://www.australiasevereweather.com/photography/photos/1997/mb19970323.html
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Offline Michael Bath

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Re: 29th March 2008 and 23rd March 1997 - A comparison
« Reply #1 on: 31 March 2008, 10:27:25 AM »
Good pick up Jimmy - there certainly are similarities in the weather setup with the MSL charts even pretty much the same.

There are two Storm News articles for the 23 March 1997:

http://australiasevereweather.com/storm_news/1997/docs/9703-01.htm

http://australiasevereweather.com/storm_news/1997/docs/9703-02.htm


The new version of the plotter for archived GFS datasets does not allow plotting of surface variables anymore so some maps are plaotted at 925hPa instead. Perhaps I'm doing something wrong ?
http://nomad3.ncep.noaa.gov/cgi-bin/pdisp_6p_r1.sh






GFS Analysis Sunday 23/03/1997 06z

Instability: Lifted Index

Relative Humidity: 0300 / 0500 / 0600 / 0700 / 0850 / 0925

Temperature: 0300 / 0500 / 07000850 / 0925

Winds (knots): 0200 / 0300 / 0500 / 0600 / 0700 / 0850 / 0925 







GFS Analysis Saturday 29/03/2008 06z

Instability: CAPE / Lifted Index

Relative Humidity: 0300 / 0500 / 0600 / 0700 / 0850 / 1000

Temperature: 0300 / 0500 / 07000850 / 1000

Winds (knots): 0200 / 0300 / 0500 / 0600 / 0700 / 0850 / 0925 / 1000


Download the maps and see how you think the setup compares.

Michael
Location: Mcleans Ridges, NSW Northern Rivers
Australian Severe Weather:   http://australiasevereweather.com/
Lightning Photography:   http://www.lightningphotography.com/
Early Warning Network: http://www.ewn.com.au
Contact: Michael Bath