Wind speed percent offset

You took the words right out of my mouth. :grinning:

I think giving users options on is a good thing, that is why WeatherFlow has a wind direction offset in place.

no the direction offset isn’t intended as an option like you want to do it or not, it is intended to make small corrections to the installation when not done correctly.
Actually I think it was implemented to correct for the 180 degree correction that is needed in the southern hemisphere. Once implemented it was probably very easy to allow users to make small adjustments.
You cannot use it to “correct” the direction because you have trees on one side of the tempest. (Which hopefully doesn’t even have a lot of influence on the measured direction, just on the speed)

You have that option of course via the feature request and vote path, but don’t hold your breath given many requests with a ‘lot’ of votes going nowhere for literally years.

Again, a third party integration like weewx can add these unusual bells and whistles to your setup if you’re willing to set one up. I’m sure other software packages can do similar custom tunings etc.

But I still personally think it’s silly. As an engineer I want gear to report what the sensors read, and I want the sensors to report truth right out of the box with no kludges needed.

In a one sensor suite system like the Tempest you need to optimize for wind (10m) or temperature (2m) when you site things. If you want a two sensor suite, there are lots of them out there from other manufacturers. Maybe you can score an old Air+Sky from somebody. Those still work too.


A GUI based setting with a wind rose and rings equaling points of gain. Ten degree points on each ring representing 36 tuning points.

Where this comes into play is being able to set a “wind gain” multiplier up to a max of perhaps 5 in whatever direction you want. Say your sensor is on your roof at a height of 22 feet. Approximately 60 feet away is a row of pine trees that are 90 feet high. The wind shadow will really cut down on gusts before the effects of the trees so more gain would be needed in that direction. In this hypothetical example, let’s say to the south there are no obstructions so the gain in this area would be zero.

Like a parametric equalizer used to tune a sound system to a room for flatter response, this feature could be used to compensate for shadows that we cannot (easily) overcome.

One other thing we cannot really adjust for is off axis wind. The ultrasonic sensor isn’t very responsive to off axis winds which are the product of serious shadowing and in rare cases being beneath a downdraft or microburst. Other types of anemometers too will not pick up these wind conditions as well but it seems like the ultrasonic sensors can really read low in off axis winds. Directly on axis, the numbers are within margin of error when compared to other instruments in a controlled environment. (i.e. wind tunnel)

Adding insult to injury, this device does NOT like being perched high up on towers. Wind is quite accurate but winds over 10-20 mph will constantly show rain due to the acoustic signature of a tower structure. Towers and guy wires are quite “chatty” in breezes and in storm conditions the short cycle vibrations register as “extreme” rain events even in clear skies.

I even recorded a 40 mph gust in near calm conditions and the culprit was a pair of sweat bees flying in and out of the gap!

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Actually, you can do that with the Tempest. You will need two Tempest sensors and have WeatherFlow designate which readings to display on the webpage.

So you have to have two TEMPEST units linked to one hub?
The only reading I would want high up on the tower would be wind.
Seems like a bit of a waste but it’s still cheap enough.

How much does it cost just to buy the tempest without the hub?

There’re several options but easiest is just to open a support ticket for this. Just explain in a few words the why . They will assist you.


Done and thanks!

I think the tower mounted unit would be best and reporting wind speed, direction, lightning and solar radiation.

The rest reported by a second unit near our garden on a fence post at six feet AGL.

Best of both worlds. We do have hawks that perch on the fences but our cattle dogs handle that problem well! :wink:

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Here is my setup in Panama City Beach. The Tempest near the ground is for rain and I named it “rain.”

And it uses the “rain” tempest as the rain sensor for the forecast page also.


It’s a bold strategy Cotton. Lets see if it pays off for them. :slight_smile: