Topic: My Ambeint Station Failing CWOP Quality Check Due To Faulty Nearby ASOS Sensor

[adamgirard]

I'm in a bit of a pickle. Over the last month the weekly emails from Gladstone are showing my station as being too warm. I've never made any calibrations on my WS-2902 thermometer, it's straight out of the box. My station is sited about 8 feet off the ground with roughly 15-20 feet of clearance from any building or trees (which is as good as I can get in my small yard)

As the error is higher at night, I'm confident it isn't due to a sun shielding issue. Around the same time my station started failing the quality check, the National Weather Service replaced the thermometer at the ASOS station about 5 miles away. They have publicly stated this new thermometer has a cold bias of 2-3F but they haven't taken any steps to replace it. I believe this is causing an issue with the analysis that's applied to my station. My station is also situated closer to the urban center, whereas the ASOS is well outside of town at the airport, and I believe this is why my station is reading higher at night, because of an urban heat island effect. When looking at other stations within a mile or so of me, they have similar temperature readings.

Obviously the NWS issue is out of my hands, and I don't think the analysis is wrong, it's just ingesting faulty information. So, I'm not sure what to do here. Do I just leave my station as is and hope the NWS replaces the faulty thermometer eventually? Or do I calibrate my station's thermometer down to satisfy the CWOP algorithm? Any advice would be greatly appreciated, thank you!

Here is my station's quality summary: https://weather.gladstonefamily.net/site/F7290
And my station's comparison graphs: https://weather.gladstonefamily.net/cgi-bin/wxqual.pl?site=F7290

Here is the NWS ASOS quality summary: https://weather.gladstonefamily.net/site/KALB
And the ASOS comparison graphs: https://weather.gladstonefamily.net/cgi-bin/wxqual.pl?site=KALB

[galfert]

The problem is not you. The problem is your closest neighbor AS107:
https://weather.gladstonefamily.net/site/AS107

On CWOP neighbors affect each other. In this case AS107 is causing you to get a bad analysis. To some degree they are also affecting KALB's analysis, but not as much as for you because you are closer.

Here you can see a good neighbor comparison and you can see that AS107 is the outlier (for temperature and humidity):
https://weather.gladstonefamily.net/qchart/F7290?date=20200824&addnl=AS107&addnl=E0122&addnl=AV597&addnl=C5574&addnl=E0288&addnl=KALB&addnl=E0250&addnl=F7874&addnl=C8192&addnl=AV496&Add+to+charts=Add+to+charts&.cgifields=addnl

Therefore my recommendation is to do one or more of these things:
- Just forget about Gladstonefamily.net analysis as it is not good at identifying who really is at fault.
- Instead use MesoWest or MADIS Surface map for QC
- Contact AS107 station owner and tell them that they are not being a good steward of CWOP with their bad data. They should take their station off CWOP until they fix their sensor.

I contact all my neighbors whenever they start having issues. You have to be nice when you reach out. Offer them help. I look up part numbers for replacement so that it is easy for them. I even offer help holding the ladder if climbing is required. In this case it seems like the owner has a Vantage Vue. I used their WU ID to determine this. That is very bad news because there is no replacement sensor. The only thing they can do is send in their station in to Davis for maintenance and it will be expensive (like +$160 I think I've heard). This is a reason I feel the Vue is a bad investment. Everything is epoxied together. You can't really do a DIY fix. You are basically replacing the entire outdoor unit. If it had been a Davis VP2 then it would be $50 and done. You can find out anyone's email by gong to www.wxqa.com and searching for the station ID under shortform search or searchCWOP. The email address will have some cryptic characters where the @ sign goes when you mouse-over (look at the bottom of the browser what the email address shows). Just do some common reasoning and you can arrive at the email address. In this case for example the email address for Mike (AS107) is mw <at> mikewren dot com.

[galfert]

KALB is a little bit bad too. You can contact the local NWS NOAA office and let them know. But I think AS107 is the bigger issue.

[adamgirard]

Oh wow, thank you for pointing that station out, I can see how it reading 110F or higher every day would cause QC analysis issues! It's a little head scratching how Gladstone shows their station as having almost zero temperature error. I'll try to reach out to that station owner as you suggested.

As for the NWS, I notified them July 28 on Twitter and their response was "We are aware of concerns regarding a cool bias with the Albany airport temperature. We are investigating with our NWS HQ instrument team." It's nearly a month later and it's still reading too cool and it's actually starting to affect the local climate data. One of our local TV meteorologists showed his frustration a few days ago posting how their faulty sensor makes it look like the month of August is running below normal temperatures but it's an artifact of the faulty sensor and "NWS is no longer responding to questions as to why it's not being replaced."

[galfert]

That is unfortunate regarding NWS getting KALB sorted out. Nicely keep the pressure on and keep reminding them every couple weeks. Ask them for an update as to when they think someone might look at this.

Reach out to the local TV meteorologist and offer them to use your CWOP station data 

https://mesowest.utah.edu/cgi-bin/droman/meso_base_dyn.cgi?stn=F7290
https://www.wrh.noaa.gov/mesowest/getobext.php?wfo=lox&sid=F7290&num=48

[adamgirard]

I reached out to the station owner and they were very apologetic, they said their house is getting painted, there’s a plastic bag over the station, and they forgot to turn the station off. That will definitely cause a spike in temperatures! They’ve now turned the station off so hopefully the QC analysis will work itself out in the next 2-3 weeks.

[SoMDWx]

Trying to sort out one's personal station settings/configuration based on CWOP can cause one to tear out your hair at best... I am thankfully near two airports, both within 4 miles of me which i use sole as my calibration / sanity checks.... I do not us any other stations since many are set incorrectly or sited wrong...

[galfert]

I reached out to the station owner and they were very apologetic, they said their house is getting painted, there’s a plastic bag over the station, and they forgot to turn the station off. That will definitely cause a spike in temperatures! They’ve now turned the station off so hopefully the QC analysis will work itself out in the next 2-3 weeks.

Hey look at that. Nice to hear of a good resolution and everyone learns from it. Thank you for the update.