Wind stopped reporting during thunderstorm

Just had a good storm come through. According to Sky, we picked up over 1.25" of rain in the last hour. The wind reporting was very low with Max wind at 15.2 mph. Winds were much stronger than that. In the middle of the event, Sky stopped reporting wind readings. The rain continued to accumulate, so I know Sky was still connected. Mounted on 5 ft. steel rod in peak of roof. No obstructions and very secure. 15 minutes later after the extreme rain changed to light, the wind readings resumed. Will the rain affect the wind sensor? The rain was very heavy and wind driven. Station#2360

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Ever since that heavy rain and wind event, the wind reading has been spotty… Mostly not working. Comes back at times, then goes blank again. We do have a light wind. Tried rebooting the hub, moving the hub, etc. Everything else is working except the wind sensor. The sky is reported as being online. I get a battery voltage reading, 0 uv reading (it’s night), and when raining, that gets reported.

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LRM_EXPORT_20180526_001441

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the sensor status show the wind is failed, so I think there is a problem on the ultrasonic anemometer .
hope the weatherflow team can help you or other member who have the experience with this issue.

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please give us a some more specifics .

did this happen during a rain event ?

was it foggy or misty ?

where are you ?

what season are you in ?

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Yes, it happened in the middle of the rain event.
Extreme rain as reported by sky. Severe thunderstorm warning… No fog
Minnesota
Late spring

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i know what the issue is but ill let weatherflow reps respond …

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Thanks for the report. Your SKY runs its raw data through a set of filters that perform real-time quality control before the data is passed to the Hub. The Hub has another set of QC filters it runs before sending the data down the path. Much of the field test process involved creating and refining these filters. But they are still not perfect (yet!). There are two specific known issues with the SKY’s wind sensor filters:

  1. In extremely strong & gusty conditions, the wind speed reading can be erroneously suppressed as invalid
  2. If large drops of water (or anything other than air) blocks the path of ultrasonic sensor signal, wind data can be degraded. In extreme cases the wind reading can be suppressed.

Fortunately, your SKY was designed to get smarter over time. As we collect more data, these filters will improve.

Looking at the graphs, the wind sensor was not functioning properly for over 5 1/2 hours after the rain stopped. Looks like it has been working properly since then. I assume that would be when the sensor dried out enough to unblock the sensor.

In extremely strong & gusty conditions, the wind speed reading can be erroneously suppressed as invalid

Out of curiosity: what is the limiting factor for the maximum wind gust reading (100 mph) ? Not that I’m expecting that strong winds in my place. There are some locations around me that get gusts of 90-100 mph occasionally.

Yes, although there is something else at play here as well. Your data may have uncovered a new bug that we should have a fix for in a future firmware build. Thanks!

There is no fixed maximum gust limit. Rather, it varies based on the history of wind speed data. One of the filters looks for meteorologically impossible changes in wind speed and the bug has to do with what the filter considers “impossible.” So, it’s an extreme (but not impossible) change in wind speed that can cause erroneous suppression. We should have a fix for that bug soon.

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2018-06-02_10-54-21

So I had a similar issue which seems to be related to heavy moisture or water sitting on the anemometers plates. We had heavy rain last night then clearing skies with a dewpoint around 70° so low levels were saturated. Winds were actually quite light 0-5 mph but my Sky was reading some of the highest winds I have measured so far. Being a meteorologist I thought what the heck it’s night time with light winds? The elevated winds readings stayed up all night and peaked at Sunrise??? Which should be the calmed part of the day. Well, I went tot he roof to check the Sky and there were huge drops of moisture all over the sensor. My guess since maximum dew formation was around sunrise the water acted light an amplifier for the light winds. As soon as the sun was up for a while and things dried out the wind readings went down even though environmental winds were increasing. Might be something to watch for those warm muggy nights after heavy rain or very dew prone mornings.

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Thanks for this report, Brad! Just wanted to follow up that our meteorologists and data science nerds are loving your data - it will help improve our filter algorithms going forward!

Same issue as wxbrad going on this morning after rain event last night.

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same issue I think, anything resolved on this?

Not yet 100% resolved, but will be improved in the next firmware release.

Currently have “Wind Failed” under the SKY’s sensor status again this morning. This time, it occurred after the heavy rains stopped. We do have calm to very light winds and a 74 degree dew point, so it is a very damp environment. The other times this has happened have all been during high wind, heavy rain events.

Hi, my sky has a Wind Failed sensor status. I have not attempted to reset anything as it was dark and raining … now I’m away at work for the day. I’d be interested in hearing if I can do something, (do I just wait for it to dry out? ), or when the firmware release arrives… thanks
Hi resolution … stopped at about 16:10 16th July
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Thanks for your help
wayne

… an hour after I posted the above it has started working again … so either a) thanks for the speedy fix, and/or b) thanks for the clever programming.

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Now, as I’m here… is there a method of knowing how much “noise” is on my sky sensor? I was noticing a bit of vibration and movement in the higher wind speeds (the sky is on a 50mm steel pipe (via its own bracket) that also has some antennas and other weather stuff). It would be nice to know the noise (as in a signal to noise ratio or similar) , and if it’s impacting measurements, so I could decide if a seperate pole is necessary.

THANKS!

regards

wayne

Likely some water pooled in the space where the ultrasonic signal is reflected. The SKY can handle some interference, but if there’s too much then it can’t take accurate measurements. Once the water dries or drips off enough, the wind data should return. We’re working on improvements to the processing algorithms, but we won’t likely be able to reduce the missing data to zero.

Looks like the same issue - too many/too large water drops cause the wind speed signal to drop out. We didn’t take any action on our end - mother nature either dried up the interfering water or blew it away!

The best test for a vibration-induced rain signal is to see if your SKY reports rain when it’s definitely not raining. If that’s the case, you probably need to shore up your multi-use pole or move the SKY to it’s own pole.

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