Rain seem off (auto-calibration system not yet deployed)



Pretty much … but that’s on a good day :stuck_out_tongue_winking_eye:
One good thing though… we each get a free chauffeur from our Parks Dept…


Just another data point. Last night had a strong rainfall. CoCoRaHS sitting on table next to Sky (not permanently mounted yet) measured 0.7" exactly. Sky measured 1.89". FYI


I was wondering when raindrops splashes on the haptic sensor it maybe register more drops ?? See this animation if so there will be more rain registered as in real…raindrops



I’ve asked that same question several times in the past year. I assume WF is attempting to take that into account with the self-calibraiton.

@dsj or @WFsupport should be able to lend some insight on that.


@btst.online Ok thanks for letting me know .


Just wanted to add my report as well. Last weekend while out of town, we had a little over 1-1.25" of rain by most accounts, and my sky reported over 8".


Lots of rain this morning, extreme at times.
Here is my findings.

Vantage Vue 29.8 mm
Analog rain collector 1 : 30 mm
Analog rain collector 2 : 29/30 mm
WeatherFlow 86.2 mm !


I’m wondering, my Sky unit’s first experiences with rain were relative monsoons. Will that affect its algorithm going forward? I received my WeatherFlow units just before what’s being called “the most active weather” in this part of Wisconsin all summer, including 19 tornadoes an hour to our south on August 28. Sky measured 12.8 inches of rain that day when we actually had about 4 inches, and 7 inches yesterday when we had 2.46. But do these downpours skew the learning curve for rain measurements going forward?


The learning is not just a one shot thing. It will be something that adapts as it goes. Will it affect during those periods ? For sure but when you come to ‘calmer’ seasons, it will adapt again.


First good rain event today.

I must say… The Sky performs extremely well.
When I take a look at the surrounding stations and official stations, they give exactly that much rain as my Sky.

My Acurite rain gauge needs a calibration. Gives way to much. :joy:

My Sky:

Surrounding dtations:

My station is in the North of the Netherlands and in the light green area.

Curious what it will do when it rains much harder. But untill now it’s performing great.


lucky me, I’m still in the area with zero rain. Will probably change soon.


Had our first real rain event since install. Sky 3.63
Ambient WS-2902 1.42
Acurite 5N1 1.27
These are in inches, and it was a monsoon!
Will give it some time👍


Absolutely. Rain hitting the SKY is a very stochastic process. Splash is just one of several factors that can affect the haptic sensor’s signal. We’re working through all of them as quickly as we can.

Look for a new firmware update that will enable another improved rain sensor calibration coming soon…


I’m having trouble buying this. Yesterday, we had our first little thunderstorm since I installed the Weather Flow Sky. Results:

Rainwise tipping bucket #1 - .15"
Rainwise tipping bucket #2 - .14"
Cocorahs gauge at home - .15"
Cocorahs at school (6 miles away) - .15

Weather Flow - .35"

My question is this, the Weather Flow is supposed to self calibrate, but based on what? How does it know if it’s wrong in the first place? My Station is # 4711 if that matters.

I should mention that in the two weeks the station has been installed I have had zero false rain reports.


Expecting 3” on Sunday. How many feet will my gauge report?


And what about hail?

How does the Sky respond on impact of hail.

We had a shower yesterday with some hail between the rain.
At that moment the Sky reported extreme precipitation for a verry short while. But I have the feeling my rainsensor does it verry well.

3 Days with good rain events. But every time it gives almost the same amount of rain as other stations. :+1::grinning:


This should shed some light on the CL algorithm. Not especially confidence-inspiring, but it’s good information.


Could the ML algorithm be better trained using a Disdrometer? This would provide a quantitative description of precipitation for the learning data.



I thought i’d post this here…

I just had a resident jackdaw try to land on Sky, and whilst it has bird spikes, he managed to get one leg on to it. I had the notification on my phone to say it was raining, but thankfully nothing was actually registered. Could this be part of the algorithms differentiating birds feet from raindrops? :ok_hand:


Interesting idea! I sure would like to have one of those instruments . . . but the $5000-$6000 (USD) price tag puts it out of my reach.