Best time of year for west swells in Indo (Sumatra area)

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indo-dreaming started the topic in Saturday, 2 Nov 2013 at 8:56pm

Lot of waves i like in the offshore island chain of Sumatra love west swells, so the question is, is there a time of year that in theory there should be more of a chance of getting decent period west swells or even WSW swells?

Its not something ive really thought about much over the years, ive been all times of year and not really noticed any real difference but then again until recently its not something ive even thought much about and basically just surfed whats was on offer, but there is a few waves that i really want to catch at there best that break best with more west swells.

Cheers

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indo-dreaming Saturday, 16 Nov 2013 at 7:46pm

Come on Graig and thermalben.....What do you guys think?

Okay maybe straight west swells are real rare and lots of times short in period i guess created by lows or wind high up in the Indian Ocean below the Arabian sea, so i guess in theory you would get these more in the period from October to March?

But what about proper groundswells that are more WSW or SW in direction rather than real south swells what creates these?

Is it where the lows sit the further south the more south the swell direction while swells that form from further up between Africa and West Oz have more SW direction in them?

Or is it more in theory that swells should start of with more west in them then as the swell progresses and lows move east the swells go more south?

This makes sense, but watching forecast i don't recall this pattern always happening and swells seem to change direction with no real logic?

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mundies Saturday, 16 Nov 2013 at 8:13pm

Been over there in May, July and November. Last May had a solid 8ft plus full W swell, guy with a lot of seasons under his belt called it the most W swell he'd seen there, slight bit of N in it. Wasn't actually on any forecast I'd seen before we headed over, it originated from south of the Arabian Sea.

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thermalben Saturday, 16 Nov 2013 at 8:31pm

Without doing a proper hindcast on each swell event I'd imagine that a west swell in that neck of the woods - actually, in any part of Indonesia - would be very rare, and would probably originate from a tropical cyclone or an unusual cut off mid-latitude low northeast of Madagascar. 

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indo-dreaming Saturday, 16 Nov 2013 at 9:35pm

Cheers

Actually at the moment if you look at say the Mentawais forecast there is a pattern of small short period West swell(sat, sun) followed by SW swells, so those SW swells i assume would be created by the combination of the high sitting over South Africa and that low further south east of madagascar with all that wind/isobars pointing SW towards indo (just SSE below Madagascar)

Interestingly for the current forecast heading from west Java east the swell for Sat, Sun, Mon is SSW

BTW to some people it my seem a bit silly trying to suss out west swells in Indo as most of them are lower period, but that change in angle can really change things, make a fatish left, break hollow or what is normally a close out right, turn into a perfect right or a reef that even on huge SW swell never gets big enough, but on a med or even small West swell waves pop up in these areas, and the bonus is under these conditions many everyday spots get better so everyone surfs those.

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indo-dreaming Saturday, 16 Nov 2013 at 9:47pm
mundies wrote:

Been over there in May, July and November. Last May had a solid 8ft plus full W swell, guy with a lot of seasons under his belt called it the most W swell he'd seen there, slight bit of N in it. Wasn't actually on any forecast I'd seen before we headed over, it originated from south of the Arabian Sea.

Yeah I've been in Indo at some stage at every time of the year and even did a six month stint in the Mentawais and seen many different west swells, many crap even wind swells but also seen some quite solid decent period ones, but most of the time im either nowhere near internet to see how it all come together or didn't really take any notice.

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groundswell Saturday, 21 Dec 2013 at 7:08am

Was at g-land on a pretty west swell late oct-nov (97),it was out of control. I didnt check the synoptic or charts as it was pretty hard back then.
Would have been interesting to see where the low was.
G-land was a good 12-15 foot solid at the peak of it. Chickens was a good shoulder-head high and sort of linking a fair way down but pretty fast and shallow. Apparently wrong direction for there and g-land proper was closing out.
I imagine a few waves would have liked that swell all over indo. Wind was south.Not great for g-land though other spots can be alright.

In Storm-riders guide indo,- weather section it says west swells occur more wet season from cyclones south of Sri lanka in the bay of bengal, early /late season from memory. Though they spin anti clockwise so it would be a very north swell i imagine from there.
been looking at the directions they spin in the last few years, they seem really unpredictable and die out quick. Some head into Thailand or Sri Lanka-India.

http://upload.wikimedia.org/wikipedia/commons/thumb/c/c0/North_Indian_cy...

It doesnt look like cyclones come south far enough for west swells, although i could be wrong.

By the way does anyone know what direction lows spin when crossing hemispheres? Do they change, die out or keep trucking?

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groundswell Saturday, 21 Dec 2013 at 7:23am

Looks like Cyclones dont travel within 5' north or south of the equator.

By the way from what ive seen good sw or wsw swells seem to be from lows off Madagascar or in that area while good south swells closer to margs river.

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groundswell Saturday, 21 Dec 2013 at 7:39am

You might find this interesting reading if you have time.
http://hackingfamily.com/cruise_info/Indian/Indian_Ocean_cruising_info.htm

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indo-dreaming Saturday, 21 Dec 2013 at 8:24am

Nice, will give it a read, some of those sailing/cruising journals are full of good info.

Yeah im pretty sure late, early and off season have more chance of West swells, but there often real short period.

The only thing is ive noticed in offshore Sumatra late season Oct, Nov also has the highest chance of crazy storms that come in from the west sometimes for weeks, strong west or north winds but often no swell, theres like a time when SW swells just go dead and these crazy storms come in, i guess in a way the start of the wet season, but there is far less difference between wet/dry season in west/north Sumatra.

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indo-dreaming Saturday, 21 Dec 2013 at 8:27am
groundswell wrote:

Looks like Cyclones dont travel within 5' north or south of the equator. .

Indo has Earthquakes, Tsunamis, volcanos, floods, mud slides, even fires...but luck for them no Cyclones.

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groundswell Saturday, 21 Dec 2013 at 12:45pm

Yeah lucky, you know there are still cyclones in south Indian too, around west of Madagascar, which if powerful enough could probably provide decent west cyclone swell. North only gets around 6 average a year or more if in La Nina. That year i spoke about at g-land(98)was el nino and may have come from a southern Indian TC.
In the last year since oct 12 there has been 10 tropical cyclones west of Madagascar, one south west of Sumatra so far with more to come.

http://en.wikipedia.org/wiki/2012%E2%80%9313_South-West_Indian_Ocean_cyc...

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groundswell Saturday, 21 Dec 2013 at 12:49pm
indo-dreaming wrote:
groundswell wrote:

Looks like Cyclones dont travel within 5' north or south of the equator. .

Indo has Earthquakes, Tsunamis, volcanos, floods, mud slides, even fires...but luck for them no Cyclones.

I wonder which way the toilet flushes at Latitude zero.
Also if those Mentawai, Telos storms change direction or die out when crossing the equator.

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indo-dreaming Saturday, 21 Dec 2013 at 6:18pm
groundswell wrote:
indo-dreaming wrote:
groundswell wrote:

Looks like Cyclones dont travel within 5' north or south of the equator. .

Indo has Earthquakes, Tsunamis, volcanos, floods, mud slides, even fires...but luck for them no Cyclones.

I wonder which way the toilet flushes at Latitude zero.
Also if those Mentawai, Telos storms change direction or die out when crossing the equator.

ha ha...according to doctor Karl, the toilet bowl thing is a bit of a hoax..
plus i just googled it to double check http://www.livescience.com/33567-toilet-swirl-direction-equator.html

Not sure but there is sometimes similar kind of storms in Tello's as there is Mentawais, those ones that kinda dance around on the horizon all day then no matter where you are hit you at night, also when i was there in March/April got hit for a almost a whole week, storm force west winds, crap west wind swell, almost went crazy.

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groundswell Saturday, 21 Dec 2013 at 7:27pm

Stuff that. luck of the draw huh. Wouldnt want that to happen on a pricey trip at a resort especially. Pay $4000 too hang inside in your room or at the bar. Well, comfy rooms at least.

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groundswell Sunday, 22 Dec 2013 at 3:09pm


Theres a Mini tornado in Bali is this a new thing for wet season?
Some seem to think its an effect of global warming.

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indo-dreaming Sunday, 22 Dec 2013 at 8:30pm

It looks like its over land?, but i bet its not, it looks like a water spout, ive seen a few in Sumatra all far offshore over ocean

Pretty crazy things the ones i have seen look similar maybe not as big or further away and don't last long.

http://en.wikipedia.org/wiki/Waterspout

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indo-dreaming Sunday, 22 Dec 2013 at 8:40pm

Looking online it seems like it did hot Denpassar and caused a little damage, some say it started offshore as a water spout, always wondered if they could hit land, pretty crazy.

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groundswell Tuesday, 24 Dec 2013 at 2:08am

I didnt know spouts would act like that on land.

With those two cyclones in the indian at the moment it seems theres a straight west secondary swell in Sumba at the moment.
It might be trade swell.
Its only 1.5 feet at ten seconds though if those two linked and intensified it would be good for west swells.Would need to be higher.
The one on the right started off near Enganno then over 10 days moved to where it is now.
Very small depressions, with not much fetch imo. Even though 60 kt winds in parts.
Id bet thats where any secondary west swell came from in Sumba.

It would be more SW id say in the ments.

It seems Aceh and the Maldives have more swell with good period but that could be from those other systems in the 40's
Hard to tell.

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thermalben Tuesday, 24 Dec 2013 at 6:44am
groundswell wrote:

With those two cyclones in the indian at the moment it seems theres a straight west secondary swell in Sumba at the moment. It might be trade swell.

Trade swell is out of the east. I've never heard a colloquial term used frequently for westerly swells in the tropics but it's probably more akin to a monsoon swell (as that would most likely be the weather pattern responsible for it).

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Craig Tuesday, 24 Dec 2013 at 9:17am

And re the toilet bowl spinning water theory in different hemispheres, yes it is false.

For the Coriolis Effect to kick in you need the process in which you are examining (water down a toilet bowl) to take at least half the length of time for the Earth to rotate once, ie 12 hours.

So if the toilet water took 12 hours to flush, it would start to feel the effects of the Coriolis Force, but any less, like less than a minute is as per normal, and there'll be no effects.

It's just the shape of the bowl and the region in which the water is injected that makes it spin.

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morris Tuesday, 24 Dec 2013 at 10:04am

Tell that to Bart Simpson!!!

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groundswell Tuesday, 24 Dec 2013 at 5:03pm
Craig wrote:

And re the toilet bowl spinning water theory in different hemispheres, yes it is false.

For the Coriolis Effect to kick in you need the process in which you are examnining (water down a toilet bowl) to take at least half the length of time for the Earth to rotate once, ie 12 hours.

So if the toilet water took 12 hours to flush, it would start to feel the effects of the Coriolis Force, but any less, like less than a minute is as per normal, and there'll be no effects.

It's just the shape of the bowl and the region in which the water is injected that makes it spin.

Thanks, would be more noticeable at the south and north poles you think?

thermalben wrote:
groundswell wrote:

With those two cyclones in the indian at the moment it seems theres a straight west secondary swell in Sumba at the moment. It might be trade swell.

Trade swell is out of the east. I've never heard a colloquial term used frequently for westerly swells in the tropics but it's probably more akin to a monsoon swell (as that would most likely be the weather pattern responsible for it).

Thanks i did mean the westerly monsoons could have made that west swell.

Speaking of those cyclones, the Seychelles seem to be copping a lot of that swell with the SE long fetch pointing straight at them.
Reunion is copping a bit but i doubt it would wrap in enough to st leu to be offshore with those winds but with the Seychelles the winds are north so offshore in many places copping the swell.

Those islands are meant to be pretty fickle and full of pirates hiding out these days.

The cyclones are meant to be dieing pretty quick though.

Heres a story on west oz cyclones in indo-
http://balisurfstories.wordpress.com/2011/01/31/the-degradation-of-surfi...

Seems a few cyclones could form soon between Broome and Darwin.

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Craig Tuesday, 24 Dec 2013 at 9:38pm

Yes, effect would be stronger towards the poles.

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indo-dreaming Wednesday, 25 Dec 2013 at 10:32am
groundswell wrote:

Heres a story on west oz cyclones in indo-
http://balisurfstories.wordpress.com/2011/01/31/the-degradation-of-surfi...

It took me a few days to click on that link, i kinda get put off by anything with the word Bali in it, but that website/blog has some really good interesting articles, there is even a few little bits and pieces regarding possibility of waves the south china sea. (even if more for the novelty factor)

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groundswell Sunday, 29 Dec 2013 at 1:31pm

I like the satire post of garbage he wrote to the newspaper in there somewhere.

Looks like one day of swell from this cyclone. pretty active at the moment up there.

http://au.news.yahoo.com/thewest/a/20510988/port-hedland-evacuates-due-t...

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groundswell Friday, 3 Jan 2014 at 3:56am

Mitchel Rae says he surfed 8 foot plus nusa dua sometime in the last few days, id guess it was from Catrine (not katrina -the hurricane).
I picked it JUST from looking at earth over a few weeks ago and the wind patters between broome and darwin suited a cyclone forming.
It needed to be more offshore though to get bigger and better.

Earth could be great for personal swell predictions in areas like this. Also ive found cyclone swells get less picked up by GFS and many surf forecasts. Sometimes cyclone swells near port headland or Madagascar are region specific imo and only last a day or less. One i surfed lasted two hours.