Topic: Can someone comment on my MADIS QC summary?

[bbowers]

Just got the email today saying it was available... everything looks good, I think... I adjusted the barometer today to be more in line with the local airport SLP and that definite helped... just wondering about the wind I guess... I know I sorta eyeballed my direction on the thing, not sure how to read the QC for that...

http://weather.gladstonefamily.net/site/D8530?tile=10;humidity=0#dewpoint

[DanS]

For the brief 3 days I had Madis QC, I was getting the green 2 thumbs up on all sections but nothing for the wind section. I took it as meaning that they can't QC wind because it varies so much from location to location like rain does. There was a red comparison indicator however in the "7 Day Vector" display along with my indicators but that's it.

[neondesert]

Your data looks good to me so far.  Two thumbs up, 100% MADIS QC score and a green check mark are as good as gets.  

I would watch things over time as you accumulate more data.  Try not to become obsessed with chasing perfect
scores.  If you do, you'll drive yourself insane!  Everyone, even Airport ASOS sites, will fail checks from time to time.  Right now
the McCarran Airport ASOS has a big red X next to Dewpoint with a MADIS rating of 95%.  
However, if you are consistently failing MADIS QC (thumbs down) then you will want to look into the cause.

As far as your wind direction is concerned, you will want to ensure your wind sensor is aligned with True North not magnetic.

[C5250]

Just got the email today saying it was available... everything looks good, I think... I adjusted the barometer today to be more in line with the local airport SLP and that definite helped... just wondering about the wind I guess... I know I sorta eyeballed my direction on the thing, not sure how to read the QC for that...

http://weather.gladstonefamily.net/site/D8530?tile=10;humidity=0#dewpoint

Wind is so variable and so highly dependent on siting that it is very difficult for that to match up unless you have a near perfect location. So there isn't much point in getting too worked up about that. The other parameters look good, but you really need at least 30 days, or so of data to really know how close you are matching what MADIS expects.

[bbowers]

Very good, I'll keep an eye on it. Thanks guys!

[bbowers]

Also, can someone explain to me how to interpret the graphs? I'm a little lost as to which is which and what lines I need to look at...

[JACK10562]

The blue lines are your actual data, the red lines are an analysis, based in part on data from nearby station reports. As far as the wind deviation, the graph seems to indicate your wind direction is pointing too far to the east.

[AridZona]

Also, can someone explain to me how to interpret the graphs? I'm a little lost as to which is which and what lines I need to look at...

If you're talking about the numbers given, the "Average error" is the mean sensor error (compared to the MADIS analysis - the red line on the graph) during the analysis period.  If I understand the "Error Standard Deviation" correctly, it indicates how far apart the data points are from the mean.  For example, readings of 50 degrees and 100 degrees would average out to 75 degrees....but so would readings of 73 degrees and 77 degrees.  The mean would be the same for either, but the standard deviation would obviously be much higher for the 50/100 degree data points.

[jay_hoehn]

But, the analysis is only good if you have stations near you.  I can't seem to get the check mark for dew point ever.  The problem is they are comparing my data with the closest station, 42 miles away and 3000 feet lower in altitude.  Not sure it is a fair comparison.  Here is my site:

http://weather.gladstonefamily.net/site/D4624

Jay

[AbuMaia]

Here is a nice script that does a good job of explaining and displaying your data: CWOP Data Quality

So how do you use it? Or is it just there to look at?

[bbowers]

I adjusted my stations direction to accommodate for "true north vs magnetic north" I'm still seeing wind speed/direction errors... weird.

Date   UTC                  Alt (mb)   Temp °F   DewPt °F   Wind Dir   Speed knts
05-OCT-2011   Errs   0/267    0/267    0/267    5/267    5/267

[mackbig]

I went through my emails from them, I can not find a single error in my wind.  However your overall rating is 99%, so I wouldnt be too worried.  I "only" do 142 updates per day.

Andrew

I adjusted my stations direction to accommodate for "true north vs magnetic north" I'm still seeing wind speed/direction errors... weird.

Date   UTC                  Alt (mb)   Temp °F   DewPt °F   Wind Dir   Speed knts
05-OCT-2011   Errs   0/267    0/267    0/267    5/267    5/267

[racenet]

Here is a nice script that does a good job of explaining and displaying your data: CWOP Data Quality

So how do you use it? Or is it just there to look at?

Personally, I don't use it. It is pretty much useless.