[wxqc] Temperature Measurement Problems

[Jeffrey Mack]

I recently installed a Davis Vantage Pro2 aspirated weather station and
began collecting data and feeding it to CWOP. So far, my temperature data is
not meeting the CWOP quality goals determined by comparing my measures with
predicted values for my location. The neighborhood we live in has many tall
oak trees and our yard backs up to a wooded forest preserve area. I situated
the Davis temperature and humidity sensors on a 5’ post approximately 50
feet from the edge of the wooded area and about 35’ from our house. The
anemometer is attached to a tv antenna mast on our roof about 30’ feet up.
Presently this site is in full sunlight from approximately 10 AM to about
3:30 PM. In the morning hours the site is shaded by our house and in the
afternoon it is shaded by the woods.

 

Our temperature readings are consistently below the predicted values with a
noticeably bigger difference that often occurs beginning around 12 noon
local time. However the nearest other reporting site  (1 ½ miles away),
DuPage Airport, reports temperature that follow our readings noticeably
closer than the predicted values. How are the predicted data in the analysis
calculated? And are my readings possibly more accurate due to the use of an
aspirated temperature shield vs. nearby stations using  non-aspirated
shields which may tend to maintain more heat as the day goes on? Or am I
simply being affected adversely by the proximity of the wooded area. But if
that be the case, why is DuPage closer to my readings than to the predicted
readings? 

 

I am curious about how one assesses the quality of a temperature reading in
general. If one measures temperature in an area where there are numerous
trees, is this reading any less accurate than one taken in area without
trees? 

 

Here are links for several days to our data and analyses:

 

http://weather.gladstonefamily.net/qchart/C4066?date=20050817
<http://weather.gladstonefamily.net/qchart/C4066?date=20050817&addnl=KDPA&Ad
d+to+charts=Add+to+charts&.cgifields=addnl>
&addnl=KDPA&Add+to+charts=Add+to+charts&.cgifields=addnl

 

http://weather.gladstonefamily.net/qchart/C4066?date=20050816
<http://weather.gladstonefamily.net/qchart/C4066?date=20050816&addnl=KDPA&Ad
d+to+charts=Add+to+charts&.cgifields=addnl>
&addnl=KDPA&Add+to+charts=Add+to+charts&.cgifields=addnl

 

http://weather.gladstonefamily.net/qchart/C4066?date=20050815
<http://weather.gladstonefamily.net/qchart/C4066?date=20050815&addnl=KDPA&Ad
d+to+charts=Add+to+charts&.cgifields=addnl>
&addnl=KDPA&Add+to+charts=Add+to+charts&.cgifields=addnl

 

http://weather.gladstonefamily.net/qchart/C4066?date=20050814
<http://weather.gladstonefamily.net/qchart/C4066?date=20050814&addnl=KDPA&Ad
d+to+charts=Add+to+charts&.cgifields=addnl>
&addnl=KDPA&Add+to+charts=Add+to+charts&.cgifields=addnl

 

http://weather.gladstonefamily.net/qchart/C4066?date=20050813
<http://weather.gladstonefamily.net/qchart/C4066?date=20050813&addnl=KDPA&Ad
d+to+charts=Add+to+charts&.cgifields=addnl>
&addnl=KDPA&Add+to+charts=Add+to+charts&.cgifields=addnl

 

I’m sure there’s a lot that I don’t understand about what is happening here
so I will appreciate any help and suggestions to improve both the quality of
data that I am providing and my understanding of the science.

 

 

 

 

 

 

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