Topic: Siting question - Where to put my sensors

[charles_slc]

My Ecowitt sensors have started arriving, now to figure out where to put them. 
WS68 - mechanical anemometer
WH40 - rain gauge
WH32 - outdoor temp (temporary till WH32EP comes in)
GW1000

According the the CWOP-Siting.pdf doc I ran across, the "ideal" locations are

Temperature / Humidity Sensor
• Should be placed on a patch of level ground, over a surface representative of the area.
[Avoid rock/concrete and dark-colored surfaces, roofs, or irrigated lawns].
• Should be mounted in a ventilated radiation shield.
• Height between 4’ 1” and 6’ 7” above ground (1.25 – 2.0 m)
• Place sensors at a horizontal distance of 2 times the height of the nearest object (tree,
structure, etc). [Example: 40 feet away from a 20 foot tall tree].
• Keep away from other sources of heat such as chimneys, air vents, air conditioners, etc.

Anemometer
• Ideally mounted at 32.8 feet (10 metres) above ground level.
• Ideally placed at a horizontal distance of 10 times the height of the nearest obstruction.
• When placed on the side of a mast (rather than at the top), the sensor should be placed
on a horizontal boom extending outwards from the mast, at a distance of 3 times the
mast diameter. [So, if mounted on a 2-inch diameter pole, the boom should extend out 6
inches away from the pole].

Rain Gauge
• Ideally mounted at a height of 4 to 6 feet above the ground.
• Ideally located at a horizontal distance of 4 times the height of the nearest obstruction.
• Ensure the gauge is mounted level to the ground, away from any horizontal surface that
can introduce rain-splashing or surrounding snow buildup.

And while it gives some examples of good & bad compromises in a suburban setting.  I could use some advice from the guru's here.

This is looking south toward the back of my house.  Planning to put the anemometer on a 10'+ gable mount on the second story (and yes I know it will need grounding)


This is from the back of the house looking north..



And this is from the east side of the lot looking west


By request, google maps view


By request, a summer photo of the trees (best I've found so far)


Originally I was thinking rain gauge & temp sensor 5-6' high on a post in basically the middle of the back yard.  But reconsidering since my lawn is irrigated.

Wondering if the top of the basketball pole might be a decent compromise.   Also before anybody asks, the "deck to nowhere" goes to above ground pool in the summer. 

Thoughts? Advice?

Thank you!

[galfert]

Google Maps satellite view helps.

I'm also trying to envision those trees with leaves.  Got any summer time pictures?

[havtrail]

Your rain gauge horizontal distance seems wrong. Fig. 10 of the CWOP siting guide shows a distance of 5 feet horizontally from a 10-foot higher obstruction (fence). That's 1/2 the relative height, not 4 times the relative height of the obstruction. The angle of the "clear space cone" above the gauge should be 63 degrees or less above horizontal. That should make things easier, or at least not as bad looking, for you.

Rich K.

[charles_slc]

Google Maps satellite view helps.

I'm also trying to envision those trees with leaves.  Got any summer time pictures?

Added to the original post

[charles_slc]

Your rain gauge horizontal distance seems wrong. Fig. 10 of the CWOP siting guide shows a distance of 5 feet horizontally from a 10-foot higher obstruction (fence). That's 1/2 the relative height, not 4 times the relative height of the obstruction. The angle of the "clear space cone" above the gauge should be 63 degrees or less above horizontal. That should make things easier, or at least not as bad looking, for you.

Rich K.

I copied & pasted the text from the guide, but good to know.

[galfert]

One neat thing you can do is go to Google Maps and turn on the 3D and then do fly overs and pan around into different angles. This helps you visualize where trees and buildings can block rain collection if there is enough sideways wind. This is also important to try and keep your radiation shield mostly in the sun as much as possible.


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Below attached was my attempt to attach an animated gif but it didn't work.

[charles_slc]

One neat thing you can do is go to Google Maps and turn on the 3D and then do fly overs and pan around into different angles. This helps you visualize where trees and buildings can block rain collection if there is enough sideways wind. This is also important to try and keep your radiation shield mostly in the sun as much as possible.
Below attached was my attempt to attach an animated gif but it didn't work.

Oh that's google earth...not maps...and I just realized it's my house 

But it's pretty old, that's before we bought the place and we've been here 4 years now. 

The trees are bigger now. 

[charles_slc]

Your rain gauge horizontal distance seems wrong. Fig. 10 of the CWOP siting guide shows a distance of 5 feet horizontally from a 10-foot higher obstruction (fence). That's 1/2 the relative height, not 4 times the relative height of the obstruction. The angle of the "clear space cone" above the gauge should be 63 degrees or less above horizontal. That should make things easier, or at least not as bad looking, for you.

Rich K.

Ok, I copied and pasted from the 8 page guide...just found the 88 page full version.

[galfert]

88 page full version??? Link please. I think I've only seen the 8 page version.

My screenshot is not Google Earth....it was done in Google Maps. It seems though that Google Maps has in some ways parts of Google Earth built in. All you do is click on the 3D button on the map and you can fly around. It is helpful to know how to use the mouse wheel and the combination of the Shift (or control) key with the mouse to move in all possible directions.

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Even if the image is old, it probably is helpful.

[charles_slc]

88 page full version??? Link please. I think I've only seen the 8 page version.

https://www.weather.gov/media/epz/mesonet/CWOP-OfficialGuide.pdf

My screenshot is not Google Earth....it was done in Google Maps. It seems though that Google Maps has in some ways parts of Google Earth built in. All you do is click on the 3D button on the map and you can fly around. It is helpful to know how to use the mouse wheel and the combination of the Shift (or control) key with the mouse to move in all possible directions.

Even if the image is old, it probably is helpful.

I don't see that in my google maps    And I do use chrome

[davidmc36]

Might be under the layers icon, top right.

[galfert]

At the bottom of your Google Maps it clearly says "3D Earth not available." The most common reason for this is that your Chrome browser does not have hardware acceleration turned on. To enable hardware acceleration in Chrome follow these steps...

- Chrome Menu (3 dots on top right)
- Settings
- Advanced
- System
- Turn ON "Use hardware acceleration when available"

If you do already have this turned on then your computer's graphics is not powerful enough or you do not have the best graphics drivers installed to support hardware acceleration.


PS - Thank you for the 88 CWOP guide. I do remember now reading this a few years ago. I had though forgotten about it.

[ramblinche81]

My anemometer question is also site related. I am surrounded by tall trees 30-50 ft tall. In summer, there is no way to have an open or un obstructed placement, and a tower or mast off roof line is not allowed. The tree Canopy fully blocks views in all directions once leaves are out..

Is it a waste of $ and data to have a poorly sited wind gauge ?  My pws set up seems incomplete without wind measurements.

My guess is the trees limbs greenery will create turbulence that makes wind direction eddy currents and I will have modified speeds with spinning swirling directions.

Feedback please and thanks in advance.

[galfert]

Your weather...is your weather and that is real. Your weather station would indicate your micro climate.

Whatever wind you experience would have a direct correlation to the weather nearby in an open field.

You should run a weather station for you to have information about your weather.

But of course you always want to do the best that you can to improve the situation with the best siting possible.
 

[TrugWX]

Is it a waste of $ and data to have a poorly sited wind gauge ?  My pws set up seems incomplete without wind measurements.

I did not install the anemometer at my current location 4 years ago (although I am considering it now). I am more interested in recording and analysing the pressure, temperature and rainfall data than the much less accurate wind data.