Page 1 of 1

Big Swells

Posted: Fri Sep 23, 2005 10:39 pm
by chris_010
Just curious as to how often the east coast of aus would experience massive swells of over 20ft? Maybe the old timers can recall the last time something like this occur? What would be needed weather wise in our region for such an event to occur, ben?

Posted: Sat Sep 24, 2005 6:55 am
by birubi
depends how you mesure that 20ft if your measuring down the back harcore style then never

Posted: Sat Sep 24, 2005 7:07 am
by Jamoe
ON the wall at my parents place at terrigal we have a picture of a freak 30ft wave breaking off The Haven around new years 1985. it is massive, completely unfathomable, especiually if your used to what terrigal is normally like

Posted: Sat Sep 24, 2005 11:36 am
by thermalben
Large East Coast swells are generated by either East Coast Lows or Tropical Cyclones (or a significant Tasman Low if it's positioned favourably). These are much different to the swell generating systems of the Southern Ocean, and therefore require a different set of circumstances to evolve favourably for us to receive large swells. That is, they need to to be near-stationary for a couple of days and surface wind speeds need to be very strong. Also, as these systems usually occur as "one-off" events, we're much more likely to see waves in this size range if the swell source (ie the low) is located very close to the coastline. Unfortunately, this usually results in a lot of rain and windy conditions at the same time.

Compare this to WA - they're on track for a potential 20' swell later next week (Fri/Sat), but the primary swell generating system is expected to originate several thousand kilometres away. However, the key difference here is that several strong frontal systems are likely to precede the main low in the 3-5 days prior, so the ocean will already be very "active", thus requiring less effort to generate very large wave heights.

Posted: Sat Sep 24, 2005 11:41 am
by macca202
so in summary we should drive west these holidays?

Posted: Sat Sep 24, 2005 1:26 pm
by thermalben
Yep. WA, SA and Vic are looking really good for the next two weeks. Really, really good infact.

Posted: Sat Sep 24, 2005 4:37 pm
by chris_010
Ah cheers for that :)

Posted: Sat Sep 24, 2005 7:04 pm
by halfy
guess its a bad time to be headin north............

ah nips

Posted: Sat Sep 24, 2005 7:56 pm
by macca202
if got a temporarily screwed toe so i can't go for a surf anyway for the next few days. i really should start wearing shoes when i play touch footy, but then everone gets pissed off cos i'll pass on the injury :twisted: