As I pointed out when I referenced that site.. it is an incomplete data set. It is based on what forecasts a group of people collecting in a limited set of time. For the most part, there is enough data there for you to get a general feel for most of the patterns. There are clearly holes in the forecast collection--zones routinely drop off, and I've seen it post nothing for over 24hours as well. The charts aren't as reliable as the forecast app either. Look at them and you will see some obvious discrepencies. Things like one chart only shows two occurrences of light and I have seen it forecast 5 times where the chart says null. The tracking of fire does not match up between the data collected for both charts--one shows instances that aren't in the other. But what it shows in the 3 day forecast calendar IS accurate, and you CAN use it to get a good feel for when to expect to find the weather popping if you use ti enough. The more you track it, the better you will get at setting aside the time for the weather you are after.
As for it only coming up in Cape Terrigan for Windsday right now, that's because (as I clearly explained earlier) it is November 9th on the game calendar, and is therefore out of season (2nd month of Fall). When it is in season, you wil see it forecast in multiple zones within the three day window--sometimes back to back in the same zone (noted I saw it do this morning as the season was ending). When in season, you can hit it a lot as back to back cycles, or at least with only 1 or 2 game days between them. Granted, sometimes it means switching zones....but with VW and OP's, it only takes a few minutes to move between them.
The bigger points are, that it is on a cycle, it is trackable, and there are tools available to help you track it.
Even though it may not show a zone in the forecast--it doesn't necessarily mean the weather is not in the forecast for that zone. But once you get accustomed to the patterns, you may get a feel for when it may be a good time to check some of those other zones as well. The trick is to actually take the time to actually do it.
And as for Mt Z......I got several cycles of fire there when I was working on trials with people and doing TAU missions (footprint search, getting lightning cell, and such). So, IDK why you aren't seeing it....perhaps because it wasn't in season at the time you were looking for it. Again....it boils down to being in synch with the pattern. The same goes for other elements too. Grauberg goes through it's phases of heavy thunder---not the best time to go there for wind at those times. Attowha has a similar shift between earth/wind. It's all cyclical, just have to track it and plan accordingly.