[wxqc] CW4870 Temperature

Thu Jan 5 09:03:13 EST 2006

Thanks, I still have a lot to learn, only now I don't have Engineers to make
recommendations about siting and the county footing the expense of shelter,
power, and phone lines out in the open.

The QC report here is much more in-depth than maintaining min/max and
comparison points-in-time readings. I gather that after a few weeks will be
a better picture. I hope to get a handle on what the report is really
saying. Distance to other stations and (as with anywhere) there are unique
dynamics of the great valley that will leave me scratching my head.
Weatherbug has some units closer to me than CWOP, but that don't help I
guess.

-----Original Message-----
From: Dave Helms [mailto:dshelms at comcast.net] 
Sent: Wednesday, January 04, 2006 10:33 PM
To: Charles M. Owen
Cc: 'Discussion of weather data quality issues'
Subject: Re: [wxqc] CW4870 Temperature

Hi Charles,

Sounds like you have the sensor siting well in hand.  Russ has a 
radiation resource  page  you may wish to visit:
http://www.wxqa.com/shields.html

Peet uses the passive shield shown in these pages and I think it is a 
good replacement passive shield for the La Crosse:
http://www.onsetcomp.com/Products/Product_Pages/temperature_pages/solar_radi
ation_shield.html
http://www.provantage.com/davis-instruments-7714~7DAVS008.htm
http://www.metdata.com/radiation_shield/rad_shield.htm
http://www.ambientweather.com/77rash.html

Dave
CW0351

Charles M. Owen wrote:

>I will try to get a picture up, but currently I have no daylight hours
>available to get a picture. 
>
>I have some modest experience from my ozone forecasting days when I set up
>equipment at my county's ozone sites. I had "real" NIST temp probes and
such
>at my disposal at that time.
>
>My current site is not quite as good as those monitoring buildings due to
>some limitations I currently have. My temp/RH/Sending Unit is at 2m between
>the anemometer (at about 10m) on the house and the rain gauge as far out in
>the yard as I can place it. I guess I could get an R.M.Young 5 platter
>shield at some point.
>
>-----Original Message-----
>From: dshelms at comcast.net [mailto:dshelms at comcast.net] 
>Sent: Tuesday, January 03, 2006 2:26 PM
>To: Discussion of weather data quality issues;
>wxqc at lists.gladstonefamily.net
>Cc: Charles M. Owen
>Subject: Re: [wxqc] CW4870 Temperature
>
>Hi Charles,
>
>Welcome to the group!
>
>We have seen some radiation shield problems with the LaCrosse stations in
>the past, especially the WS2300.  These problems have been mitigated
>successfully  with replacement of the LaCrosse "cone" shield which has very
>high restricted ventilation, with a standard "bee hive" or Gill shield
who's
>horizontal plates allow the sensors to "breath" without solar
contamination.
>
>In the limited period of record for your station's operation, we are seeing
>a high "negative bias" (e.g. warmer than the surrounding stations, after an
>elevation correction).  This is very preliminary info, and it will take
more
>time to get a better picture or performance.
>
>To help us better assess your station's performance, could you please
upload
>digital pictures of your weather station sensors to the FLICKR page using
>the instructions on this page:
>http://mywebpages.comcast.net/brookevilleweather/flickr_setup.html
>
>
>Thanks,
>
>Dave
>CW0351
>
>P.S.  Hey Philip:   I don't think the most recent FLICKR "CWOP Metadata
>Group" member's pictures with "CWOP" tags are getting embedded in the WXQC
>station pages.  
>
>
> -------------- Original message ----------------------
>From: "Charles M. Owen" <cmowen at att.net>
>  
>
>>Hi, I am sort of a newbie. I have only had my Christmas present La Crosse
>>WS-3120TWC up for two weeks. These are my first QC reports. I am 27 miles
>>from the closest known site that I am compared with. When should I start
>>worrying about these readings? 
>>
>>   DATE     UTC      SITE  *   ALT    * POT TEMP *  DEW PNT *    DD    *
>>FF    
>>                           *   (MB)   *  (DEG F) *  (DEG F) *   (DEG)  *
>>(KNT)  
>>02-JAN-2006 0813    CW4870 *1013.(-0.2)*
>>59(-6.3)*51.8(-5.3)*199.(132.)*4.34(-2.6)
>>02-JAN-2006 1037    CW4870 *1011.(0.45)*
>>60(-6.9)*53.5(-6.2)*192.(6.08)*4.34(  -4)
>>02-JAN-2006 1052    CW4870 *1011.(0.85)*
>>60(-6.9)*53.1(-5.8)*190.(8.08)*5.21(-4.8)
>>02-JAN-2006 1102    CW4870 *1011.(0.63)*
>>60(-6.8)*53.1(-5.6)*182.(135.)*6.08(-5.3)
>>02-JAN-2006 1117    CW4870 *1011.(0.63)*
>>60(-6.8)*53.1(-5.6)*203.(114.)*6.95(-6.2)
>>02-JAN-2006 1132    CW4870 *1011.(0.63)*
>>61(-7.8)*53.7(-6.2)*249.(68.9)*3.48(-2.7)
>>02-JAN-2006 1147    CW4870 *1012.(-0.7)*
>>60(-6.8)*53.5(-5.9)*206.(111.)*7.82(  -7)
>>02-JAN-2006 1202    CW4870 *1012.(-0.7)*  59(-6.9)*53.5(-4.5)*236.(
>>19)*4.34(-3.6)
>>02-JAN-2006 Errs    CW4870 *   0/87   *  15/87   *   0/87   *   1/87   *
>>1/87   
>>02-JAN-2006 Smry    CW4870 *-0.3(
>>0.5)*-3.7(2.79)*-1.9(2.76)*43.3(76.2)*-3.3(3.01)
>>
>>Note that times are in UTC. The values displayed are  'Observed (error)'
>>    
>>
>The
>  
>
>>error value is 'analysis - observed'. I.e. if your observed value is
>>    
>>
>higher
>  
>
>>than the computed value, then the error will be negative. You have to pick
>>out the reading that is in error. The row with the time of 'Smry' is a
>>    
>>
>daily
>  
>
>>summary and the data is  'mean(standard deviation)' for each observation
>>during that day.
>>
>>Graphs: http://weather.gladstonefamily.net/qchart/C4870?date=20060103
>>
>>
>>
>>
>>_______________________________________________
>>wxqc mailing list
>>wxqc at lists.gladstonefamily.net
>>http://pond1.gladstonefamily.net:8080/mailman/listinfo/wxqc
>>
>>The contents of this message are the responsibility of the author.
>>    
>>
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