Barometric Pressure off (corrected once CL system is deployed)

Thanks Gary, it’s Mount Wilson and it’s online. Thought the ID might be more sophisticated.

Langdon

Your Station ID is a four digit number.

That has to be the quote of the day! :rofl:
Thanks for the information, David.

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I tried sending you the correct I but apparently the message wasn’t long enough. ID 4561.

Elevation… To get the right barometric pressure as the surrounding stations.
But I have read dsj his post. So I changed my elevation to normal for here.

If you put in bad information, there is a possibility that will adversely impact calibration when it comes online.

The elevation of your station should be as accurate as you can find and the height of the Air and Sky should also be accurate. I understand your readings may be wrong now but I am pretty sure you want accurate readings with proper calibration.

Sure Gary.
So I changed it back to normal elevation for my region.
Will await the CL.
When I looked this morning at my dashboard, I saw that it wasn’t even that much off to other stations. :ok_hand:

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We are all anxious to see accurate readings.

Of course, I’m not sure I would recognize a good reading if I saw it. I have nothing to compare with and no way of knowing which stations are accurate.

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Well I asked a while ago for callibrating the pressure why there couldt filled in negative units for height I had to subtract 17 meters for getting the right relative/seapressure for getting it right according METAR stations atm I live virtually 7 meters below sea leavel (some really do here live below sealevel but I’m 10 meter above sealevel in real. I better couldnt make this adjustments as I read your reply ? In that case WF should have mentioned that CL should take care in the coming time that I should need to adjust my offset to sealevel.

The question was over here and a day later it was possible to enter negative values for my altitude.
Pressure Display - Station vs Sea Level

I’m having the same issue the OP was having, barometric pressure that’s often about 0.1” too high compared to 2 relatively close area airports, my Davis VP2 and area PWS. My Davis FA VP2 always seems to be extremely accurate for all parameters except very high RH where it can be a bit too low. At other times the pressure of the WF can be closer for no apparent reason. It seems the WF pressure changes can be somewhat random and inconsistent with other stations in the area. As an example, just this morning, in the same 3 hour period, my WF saw a drop of .24” while the Davis had a drop of .08”. That’s a huge, 3x difference and makes no sense. The Davis fluctuation is consistent with area airport changes.

I’m not sure if this is due to the barometer being housed in a device subject to ambient temperature changes. That might make sense. This is atypical for most barometers that would be housed indoors. My height is dialed in properly, but I can’t recall having a PWS where the pressure was off to this degree.

My temperature also seems to be typically 2 degrees low and almost always the lowest temperature in the region, including other PWS, my Davis, my Kestrel and area airports. It’s not a huge error but a bit annoying in its consistency. Typically you can calibrate a consistent error like this with a PWS, but there’s no way to do that with the WF system.

On the bright side, since its dried out here in NY, my winds have been good and consistent with my Davis, but actually better at the very low end as expected with the ultrasonic sensors.

I’m assuming that only RH has the CL system at this point? I’m not sure where the CL system pulls the calibration data from. Is it other PWS in the area or close NWS airport sites? I ask because the NWS RH/DP airport readings are often very different than the PWS in the area. I know RH is always a tough parameter to nail.

My station # is 6187.

So I thought the group & tech support might be interested in some bizarre barometric pressure behavior from my Air. I think it’s pretty well established that my Air is defective…at least I hope it is otherwise we’d be looking at what I’d think is a design issue.

You can see from the first graph the utterly nutty increase & then decrease in barometric pressure. Keep in mind the weather here is calm, no fronts, no precipitation, just a calm period in our weather. My Davis, concurrent with this same time period (as well as surrounding PWS & NWS stations) saw a change of about .01". What I find interesting is the 2nd graph, temperature, and how it pretty much mirrors what’s going on with pressure. Temperature changes like this certainly shouldn’t impact pressure changes like we’re seeing here. In fact this is why I had originally posted about the influence of temperature changes on pressure within the Air unit. It was what I had seen before with my Air. My Air also reports some unusual RH, very often running 20% high.

Now I should mention that yesterday I put the Air on a table for the purposes of taking a picture for tech support and I forgot I had left it there. So this morning, as the sun rose, the Air was exposed to the sun. Of course this explains the temperature change and it’s what I’d expect given the location of the Air at that time, but the barometric pressure is something quite different. As Spock would say, “Fascinating”. :wink:

I’m not sure why I didn’t think about this before, but I just checked the WF map for Long Island. All other WF stations I looked at show almost static pressure readings this morning. No other WF station shows anything remotely like what I’ve observed today. So that does provide quite a bit of comfort. My Air is having a nervous breakdown. :slight_smile:

Yes, something is clearly wrong with your original AIR unit - hopefully the replacement will be happier!

Fingers crossed Dave, the new unit arrived. :slight_smile:

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Will someone please explain the CL System? How does it work and how it was done?

Also with WU you must put in your station height as well, so I bet WU will adjust according to the WX System you told them you have. edited to add this sentence*

Any and all information will be greatly appreciated.

You might want to do a little searching of the archives, there have been soooooo many posts about this over the last year. A google search for “weatherflow cl algorithm” returns lots of good info at the top of the results.

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I was just asking if this calibration happens everyday or must I request it??

Only WeatherFlow knows how and when but you can learn a lot about the how and when by reading the information here.

Again, if you search the zillion threads the answer is there.

Short answer is they automagically do it for all stations after some number of days the station is online and reporting. What is calibrated when seems to vary based on sensor. You don’t have to request them to do it, it just happens.

Older versions of the sky actually reported an event when you could see when the calibration was received (used to be daily) but they took this event out some number of versions ago. Several of us have asked that it be added back in.

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Hey keep those negative comments to yourself, I did search and found that there are so many different answers, you could have said nothing or answered the question. No I cant learn how and when due to fact there are to many how’s and when’s