An actual real Coffs Harbour ECL early next week

[Karlos]

My parents always said I should have paid attention in school. I never believed 'em though until reading this thread

[thermalben]

4 day BOM forecast as of Thursday 20/7 shows that next monday 24/7 at 10:00pm there is no sign of that east coast explosion that your map shows to be occuring on tuesday Ben.

The map I posted above is the GFS numerical weather model, which is the only source that has ever suggested an ECL since day 1. To be honest, I've never been been overly confident on a true ECL eventuating from this setup, and have only tried to provide information in this thread detailing why it is a possibility.

The BOM 4 Day forecast uses the EC numerical model, which anticipates a deepening trough to run down the East Coast rather than an ECL. This is a much more plausible scenario IMO, and should result in a broad spread of NE swell in all areas.

[thermalben]

It was from bouyweather.com not sure what type of bouy that is.

OMP, that's not a real buoy, but a computer generated prediction. It is important to understand the limitations of computer generated models when comparing their data to real time surf conditions.

[craig]

It was from bouyweather.com not sure what type of bouy that is.

OMP, that's not a real buoy, but a computer generated prediction. It is important to understand the limitations of computer generated models when comparing their data to real time surf conditions.

I was always amazed that the worlds governments or whoever had actually got together and installed a system of buoys to measure rise and fall and distances between waves...... all around the whole world

YOU MEAN TO TELL ME THAT THESE ARE MERELY COMPUTER GENERATED FIGURES AND THERE ARE NO BUOYS PLANTED OFF OUR COASTLINE?!?!?!?!?

Is there one, at least, anywhere that they take any readings from?

[thermalben]

(assuming you're not taking the piss Craig!)
Yes, there are numerous buoys off the Australian coast. MHL operates a network of seven buoys of NSW's coastline, the EPA operate Qld's buoys, the BOM have one buoy in Tas and another in SA, Port of Melbourne has one in Vic and the Dept of Planning and Infrastructure operate six buoys in WA. There are numerous privately owned buoys too, but they're not usually made publically available.

[NewyBen]

It was from bouyweather.com not sure what type of bouy that is.

OMP, that's not a real buoy, but a computer generated prediction. It is important to understand the limitations of computer generated models when comparing their data to real time surf conditions.

I was always amazed

I'm always amazed at the stupidity of people who think a 'virtual' bouy is a tangible physical thing sitting in the ocean taking and reporting measurements! What part of virtual don't you understand?? And then idiots who look at them and go "Wow omg the buoys are forecasting a 50 foot westerly swell off Sydney, and offshore winds too, fark its gonna be pumping". Use the limited grey matter inside you heads dumbarses!

[thermalben]

I'm always amazed at the stupidity of people who think a 'virtual' bouy is a tangible physical thing sitting in the ocean taking and reporting measurements!

That's the thing too - they're not even "taking and reporting measurements" - all of the data displayed by Virtual Buoys is in the future, so it's "predicted" rather than "reported".

[Brand_77]

Ben you're a bloody legend!! Thanks for all the help for us wanna be forecasters. Swellnet is brilliant keep it up!!

[thermalben]

Here's one for y'all to consider. If GFS is suggesting an ECL off the northern NSW coastline at 6 days out (as has been the case in recent days), but then the model progressively downgrades the system as the nominated time frame draws near, how does this affect the forecast trend for other Australian regions around the same time?

[Nick Carroll]

Well the east coast is so skitzy and changeable compared with the general systemic flow to the nation's south and the far tropical north. It's hard to compare an Indian/Southern Ocean six day prog chart with that concerning the stupid Tasman Sea and environs.

All these forecast models have their problems, but some seem more susceptible to spazzery along the Aus east coast than others, even when they're doing a good job for West Oz or Vicco.

[One Mile Point]

It was from bouyweather.com not sure what type of bouy that is.

OMP, that's not a real buoy, but a computer generated prediction. It is important to understand the limitations of computer generated models when comparing their data to real time surf conditions.

I was always amazed

I'm always amazed at the stupidity of people who think a 'virtual' bouy is a tangible physical thing sitting in the ocean taking and reporting measurements! What part of virtual don't you understand?? And then idiots who look at them and go "Wow omg the buoys are forecasting a 50 foot westerly swell off Sydney, and offshore winds too, fark its gonna be pumping". Use the limited grey matter inside you heads dumbarses!

fuckarse i never said there was going to be 50ft westerly swell, my question was more based on how come there were waves with a westerly swell

[thermalben]

All these forecast models have their problems, but some seem more susceptible to spazzery along the Aus east coast than others, even when they're doing a good job for West Oz or Vicco.

hehe. I'd love to submit "spazzery" into the BOM's glossary.

One entry found for spazzery.
Pronunciation: 'spa-z&-eh-ree
Function: noun
Etymology: frequentative of spazz
1: when the bloody computer models keep forecasting waves we never get

[barstardos]

OK ben - here is my crack at it.
GFS is downgrading the forcast Low in to a trough due to a blocking high near stationary in the lower Tasman Sea. The intensification and blocking nature of this high is slowing the progression to the East of the large Southern Ocean Low to the far SW of of WA. It is also increasing tthe pressure gradient across the southern ocean swell window for WA, SA, Vic and W coast Tas. ie: Macking Southern ocean groundswell for these coast building from next friday.
Also winds are very good for Vic next week.
whaddya reckon?

[thermalben]

I suppose what I'm trying to get at is that most weather models are global in coverage. If a particular model is having a hard time with one system (be it an ECL, TC, cold front, upper cold pool.. whatever), then its poor modelling performance in one region means that other regions may also be off-kilter to some degree.

Classic example a few weeks ago - I got a few calls about J-Bay - everyone was getting ready to head over for the Billabong Pro, and most of the swell charts were calling a ridiculously large swell at the end of the model run (6/7 days in advance). Therefore, a few people were wondering whether they should be advancing flights to catch the swell (before the event) and packing larger boards. At that point, I hadn't been watching South Africa closely, but I knew at the time that the model that underpins most of those swell models (GFS) was having a particularly hard time with a few system in the Australasian region - so much so that I had discounted its output all together for my Vic and SA forecasts.

Based on this, I advised a few people that this "massive" swell for J-Bay probably wouldn't eventuate, and would probably remain on the smaller side of the coin (which is what happened).

My point being is that if a weather model is having a hard time in one area, you can bet that it's not coping well with most other locations. This is a very useful tool if you're heading overseas or interstate for waves. The exception to this - as Nick pointed out - is the Southern Ocean, where swell generating systems are associated with broad systems in the upper levels of the atmosphere that cover a much wider region. Therefore, even if the model continually refines itself, it usually results in a directional or timing change rather than a large swell vs zero swell scenario (like what happens along the East Coast sometimes).

[thermalben]

OK ben - here is my crack at it

Yep, pretty much it bastardos - however - the Southern Ocean storm track isn't looking great for Vic (which is a shame as winds will be good) or Tas. WA is likely to see yet ANOTHER v.large swell though, and I can think of several breaks back home in SA that will be quite tasty between next Thurs and Sun. Hmmmmm. Anyone for Gnaraloo next Thurs/Fri/Sat?

[barstardos]

thanks ben.
Ok lets just pretend we are the weatherzone forums and debate the relative merits of each model as it relates to our region and surfing.
For mine, I agree the GFS starts tripping when it goes beyond 120hrs for SE Australia - in winter... EC everytime!!
But if I rememeber rightly, GFS was better at picking up Tasman Sea and Coral Sea spazzery many times last summer. ie EC was too conservative to pick up the crazy tricks that the E coast can throw at us in the warmer months.
how does this compare to everyone elses memory of those warmer months?

[mode5707]

thursdays looking good at this stage on the synoptic maps with the low
moving eastwards giving us synoptic westerlys whilst pushing the
ne winds out to sea. I will be surfing the mostly overlooked(by outsiders
not locals) best beach break in the wollongong region if this scenario eventuates. Hopefully it is like last sunday but bigger. Photo is not of
last sunday. Fingers crossed.

[chris_010]

Definately looking to be one of the swells of the year on its way. Solid NE with west winds....god we don't get enough of em!