@Vir: There are a number of problems involved in understanding climate and how it would behave in circumstances for another planet than Earth with its current layout of continental landmasses, sizes and depths of ocean.

One is we don't really understand how Earth's climate works. There are a lot of theories and models, but many of them fall apart if we try to use them to explain the current Earth in any detail, and/or if we try to use them to explain what we understand about the geological past (this latter is a particularly major problem).

Another is that because we don't properly understand how our own planet's climate operates, when we try to use these theories and models to explain another planet's (and this has happened repeatedly in our own Solar System), they don't really work either.

So the further we get away from the current physical situation for Earth, the more guesswork is involved, essentially. (And there's a lot of guesswork involved in explaining the current situation already!)

Ocean depths different to Earth's create particular uncertainties, as it's clear there are things happening in Earth's deeper oceans that have huge effects planet-wide, but we don't really know why they happen. So when trying to look at a planet like this one, where great areas of the ocean are much deeper over far larger areas than Earth's, it gets to the point of either giving up, or just going with whatever you fancy!

Ocean currents, for example, can flow in completely different directions at different depths - a warm current might be flowing over or under a cold current behaving in this way too. Similar things happen in the atmosphere as well, so while that shouldn't be a surprise, it doesn't mean we really know why things are as they are.

If you need a south to north wind (maybe only seasonally), my advice would be simply invent what seems to you a good reason for why it happens, and if that involves something relating to Earth's climate/weather patterns, possibly only vaguely, just invoke that. If anybody's daft enough to question it, then obviously it's because it's also influenced by the planet's magical field!

If you need ideas based on what happens for Earth, I'd suggest taking a look at places online such as already suggested above here for the geological situation for Earth that's similar to your own planet, with things like the estimates for broad-scale current flows. If you can find a good-quality physical atlas showing similar things for either the past or present (which is a useful definition for "good quality"), that will be just as suitable, dependent on what you prefer.

I could scarcely let the name pass without comment!

Wasn't familiar with this, but checking around online, I gather Savage Seas was originally a series of linked adventures published in Dragon magazine in 2006-2007 for D&D. It's taken a lot of digging around, but I think the blurry map of the Sea Wyvern you mentioned, and which seems to be that shown online in places, was originally published as a loose poster-sized map in Dungeon #141, so was presumably much clearer that way. Sadly, I don't have a copy of the magazine to confirm, however!

It looks as if there were other ship plans published for some of the other vessels encountered during this campaign, judging by what I chanced-upon online (as low-res images, or simply from comments made), and I did come across what seemed to be an online conversion of the whole campaign to Pathfinder as well, but that seemed to have few images overall - aside from a blurry Sea Wyvern drawing, much as I imagine you were working from.

Nice-looking drawings, by the way!

In Egypt, as also in Mesopotamia (modern southern Iraq), the man-made thing for irrigation started very early on, so telling what's truly "natural" is no longer really possible. You get a similar effect in the deserts near both places modernly where there's been a rare, heavy rainfall recently; there's a sudden explosion of greenery and flowers in a concentrated area where the rain happened, and the immediate vicinity of the run-off, surrounded by the usual "barren" waste. It lasts for at most a few weeks, and then it all dies-off, and vanishes.

I think "chook" originated with some dialects of English. "Chuck" is a term of endearment still used in parts of northern England, for instance, which derives from the same source, as a variant on "chick" as an abbreviation for "chicken", or from "chick" as being a young chicken. Online sources seem to cover only the modern Australian option as in-use still, however.

And here was me thinking "duck down" was an urgent warning...

Well, technically, it was a Scot, James Watt, who advocated a standardised international decimal system of scientific measurements in 1783, and what we now recognise as the whole series of SI units, sometimes colloquially referred to as the "metric system", was the product of a great many people in various parts of the world over many years from the 18th to 20th centuries, with numerous variant definitions even for the metre during that time. What's now considered that metric system, the formal international adoption of the SI units in fact, didn't happen until 1960, and that Système International continues to evolve.

Sadly, there isn't a suitable metric definition for such pedantry though ??