I took some video showing the behaviour of water on the special coating. This is on a ‘Sky’ but I assume the Tempest will be similar. There is lots of discussion about the problem on this forum, you could use the search to find it. If your pole is easy to give a swing from the ground you might be able to move the water drops and see if the wind reading changes. In very strong wind they get blown off but light wind they can bobble around sitting on the lower surface. Here is one example:
cheers Ian 