Very high rainfall amounts. How to calibrate Sky?

I’m not Markus but indeed 5 liter rainfall is 5 liter on a square meter ergo
1 liter = 1 dm^3

Amount 1m x 1m x 1mm

This is 10dm x 10 dm x 0,01dm = 1dm^3 = 1 liter

I need to mention this method is not used in the weatherforecasts in The Netherlands but sometimes used to visualize the amount of rainfall mosty in buckets ( a full waterbucket has about 10 liters ) so when there was or comes rainfall during a storm etc with 40 mm they say this wil be equal by splashing rain on a square meter out of 3 full buckets assuming the bucket contains 10 liters :wink:

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Hello Eric,

yes spacesnow is right 1 liter = 1mm Millimeter . In the weather forecasts in Germany mm is used.

Regards Markus

I live in an area with few rain storms (Phoenix, AZ, USA). But, we have had a couple recently, and my Sky was off by a lot. I also have a CoCoRaHS compliant manual rain gauge. On a recent event, Sky recorded about 1.8", while my good rain gauge recorded .32". The latter is consistent with official flood control district gauges in the area.

My professional meteorology research friends say that haptic doesn’t work very well. They told me that before I got the latest gauge. I hoped they were wrong, and I suspect that the Sky could do a lot better than it is doing. Who knows.

In my case, the rain droplets are usually large to very large, due to the way our convective activity behaves.

I hope a fix comes out. I hope a fix is even possible.

John, I live in Denver and similar weather when it comes to actual rain. I am seeing the discrepancy in rain measurement.

Add me to the list of users experiencing the “WAY TOO MUCH RAIN” bug. Had a heavy rain event today and the SKY registered 5.45" of rain. Nearby stations seem to be averaging less than an inch…

Hi folks. Not sure how we missed this thread but I was just searching for something else and ran across it. Apologies for that.

As you’ve noticed, the rain sensor’s calibration can be off, sometimes WAY off. The main issue is that the calibration of the haptic sensor seems to depend heavily on the local installation conditions. The length of the pole or mast, what it’s made of, what’s attached to it, what it’s attached to. The good news is we’re actively analyzing the rain data coming from your SKY units and we’re confident there is a solution: a real-time QC and auto-calibration system.

You will likely continue to see some odd rain data for a while as we work what the humans are learning back into the machine learning algorithms that keep your stations calibrated. Thanks for your patience.

For some more reading on the subject, there is another thread discussing this same topic here: https://community.tempest.earth/t/rain-gauge-reading-wrong/930

I’ve noticed that the accuracy is fairly close for low/moderate rainfall rates, but downpours throw it off. We just had a heavy rain event. My rain gauge recorded 1 inch, while the Sky reported nearly 2.8". During the event, the Sky recorded one reading of a 14+ inch/hr rainfall rate, which seems dubious.

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Yes, I too have noticed that accuracy degrades as rainfall rates increase. My light rain events generally match neighboring station observations, but heavy rain events are WAY off. Regarding installation specifics, my SKY is installed on a heavy duty steel pole that’s about 3’ tall, screwed to a brick chimney with heavy brackets. It’s about as solid of a mounting scenario that one could expect.

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My station shows we had over 8" of rain in the last 24 hours, but the highest in the area was about 3" actual #4298

Thanks, Bill. Inaccurate rainfall is an issue many users are experiencing and something we’re focused on addressing. Please see this thread for more detailed reporting and discussion: Rain Gauge Reading - Wrong

SKY has been measuring here for several months. I know you’re still working tons of hours on fixing things, but Sky is still reporting inaccurate rain data despite months of reporting problems by many. Not good.

In past 24 hrs, rain is way off:
… WeatherFlow Sky: 12.1 mm rain
… Davis Vantage Pro 2 on same pole as Sky : 6.6 mm
… NetAtmo: 7.6 mm

Getting a bit discouraged. I would suggest you describe the firmware as BETA until things are fixed. Some measures are working better now (temp and humidity) but the standard deviation and error rates of the data is much too high across the world to be reliable.

In my view, the unit is not ready for prime time. I’m happy to continue being a beta tester as needed, however.

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Got my system a few days ago. Noticed that the rain was also very high. Last night storm produced rainfall of 9.14 inches on the Weatherflow. My Davis pro 2 measured 2.12 inches. Lighter rains the past week produced like results.

Yes, I have the same problem. My rainfall readings are constant, even during dry weather. There’s been no rain today and it’s showing 0.9 ml for the last 24 hours. Like the reports from other WF operators, the heavier the rain event the greater the discrepancy between my old gauge and my Sky.

Something must have changed after 2 weeks of raining reading fine, Ive accumulated 4.9 mm today, been sunny no rain with no wind over 24km/h

Do you realize you posted this twice?

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sorry about that my anti-virus said it blocked the first message

Hi station ID 4664 we had some very nice and need ed rain yesterday FIY WF registered 13.8mm …actual rain by visual rain gauge 9.2mm, not too far off. Thanks WF team its a great piece of equipment :+1:

2 posts were merged into an existing topic: Rain Gauge Reading Seem Off (auto-calibration system not yet deployed)

I’ve got just the opposite problem - my WeatherFlow is reading about 41% less than my AcuRite 5in1, and my old fashioned rain gauge. Interestingly enough, the AcuRite and the old time rain gauge read nearly identical rain amounts (0.51 and 1/2 inch respectively), while my WeatherFlow measured 0.3 inch of rain.

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Seeing some better rain results today. Steady, moderate rain measurements seem to be quite accurate. It’s the heavy storms here that need some work.

image

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