Culverden Recording Station

[Richard]

Over the last two months ive noticed that there's a 4dec difference most days between Culverden and what i get,i really do struggle to believe that there could be such difference, the odd day maybe,take last Saturday,Hamner Springs had NZ's high (35),i got 35 also,Culverden thats half way between 32.5 ,take yesterday, CHCH with a high of 19.8 and a strong NE wind off the sea and Culverden 18.7 with a much lighter E blowing over a warmer landmass, I recorded a high of 23C,which was something i noticed as soon as i first hopped out of the car and that was just how much warmer it was after arriving back from CHCH.
I know my recording gear is reasonably accurate thanks to now having a thermometer to help double check,also having a neighbour with a weather station that closely matches what i record,there two modern cars show similar temps also
This recording station has played up in the past,about 2 or 3 years ago there was about week long period which was in either Feb or March,cant remember which,but during this period TVNZ weather reported the Culverden had the low for NZ every day,temps of 15-17C where i was getting 26-29C,so i knew that there was something majorly wrong,the first three nights i would be thinking "what the hell",4th and 5th night i sent emails to TVNZ,had no response but on the 6th night i did a phone call to the news programmer and she said she would look into it,never heard from Culverden again for over a year after that.

I know that the recording gear has been update at this site since but i'm starting to think that it is playing up again.

Ive sent an email to MS asking them where the recording station is situated maybe this has something to do with why there's such a difference.

[Captain Salty]

i don't know if this is the same one but http://weather.gladstonefamily.net/site/93658

[Richard]

i don't know if this is the same one but http://weather.gladstonefamily.net/site/93658

Could be CS,hopefull i'll hear back from MS

[Richard]

Sunday's high on the MS site 22.7,i got 28C absolute bullshit

[RWood]

Don't know if it's the same station, but in the December NIWA stats. report there's a Culverden AWS, and its average max. readings look to be in line with Waipara, Waiau and Hanmer.

[Lacertae]

Let's hope MS will respond to your email, it will be interesting to know the full story !

[Richard]

The MS sent an email and its at this site http://weather.gladstonefamily.net/site/93658

Looking at the information i see that both Culverden Aero and Culverden Aws are at the same lat -42.7667°, long 172.8833°,but the Aero is at 174m and Aws at 181m on flat land,does this mean the Aws is 7m up a tower??

I see another site there only 2km from where i am Hurunui Aws, New Zealand (lat -42.8667°, long 172.7167°, altitude 235 metres)

Do you have access to this site Rupert?

[RWood]

The MS sent an email and its at this site http://weather.gladstonefamily.net/site/93658

Looking at the information i see that both Culverden Aero and Culverden Aws are at the same lat -42.7667°, long 172.8833°,but the Aero is at 174m and Aws at 181m on flat land,does this mean the Aws is 7m up a tower??

I see another site there only 2km from where i am Hurunui Aws, New Zealand (lat -42.8667°, long 172.7167°, altitude 235 metres)

Do you have access to this site Rupert?

Can't answer the altitude question - maybe one of the coordinates is wrong?...the Hurunui AWS is not listed in NIWA's CliFlo for rainfall and temperature as far as I can see, or in their monthly stats. report.

[Richard]

Yesterday's recording is yet another example of why i think this site figures are wrong,on MS website yesterday temp for CHCH airport (21.1) and Culverden (21.2) on a day of high air pressure,yer right,like many other inland places this area temps are simply not influenced to the same extent by coastal sea breezes.

[Razor]

Sunday's high on the MS site 22.7,i got 28C absolute bullshit

Yeah having driven from Kaikoura to Hanmer via Waiau and Culverden that day I have to agree. The tar seal was melting around Culverden, that doesn't happen at 22.7!

[Richard]

Sunday's high on the MS site 22.7,i got 28C absolute bullshit

Yeah having driven from Kaikoura to Hanmer via Waiau and Culverden that day I have to agree. The tar seal was melting around Culverden, that doesn't happen at 22.7!

Bit odd isnt it.

Spoke to a bloke from MS yesterday,great to talk to and was really helpful,he recons that these kinds of variation are reasonably common in parts of NZ ,in his case he lives in Upper Hutt and said that its common to be 4-5 warmer than Wellington.
He spoke of a new Niwa recording station next to SW7 three kms before the Hurunui pub which is two km in a straight line from me, while i was talking to him he said it was recording 21.3 at that time,so after i got off the phone i went over there to pick up the recycling bags and took the thermometer also,standing beside it,it showed 23.6,so buggered if i know.

[Manukau heads obs]

big difference from a properly screended reading and standing in the open taking a reading, where your sensor will be picking up reflected radiated heat from surfaces

[RWood]

Upper hUtt is well known for a number of doubtful claims. There's nothing wrong with the Wallaceville readings, which do naturally show a bigger daily range than Wellington - but not at the level that some out there regularly claim.

[Richard]

big difference from a properly screended reading and standing in the open taking a reading, where your sensor will be picking up reflected radiated heat from surfaces

I was out in the open in the long grass on the side of the road

[Manukau heads obs]

still though was your sensor in a double louvered stevenson screen?

[Richard]

still though was your sensor in a double louvered stevenson screen?

No but neither has the Niwa station,there's looks more like a Davis type system

[Manukau heads obs]

still though you would need to have your sensor in the same type of screen to be able to do a comparison reading
thats what I am getting at

[Richard]

still though you would need to have your sensor in the same type of screen to be able to do a comparison reading
thats what I am getting at

Yep ,i know what you are saying Brian ,the sensor readings do fluctuate when out in the wind so ive been taking the reading halfway between the highest and lowest to date,so ive been thinking how i could mount a small screen the end of the sensor wire,maybe some thin white fabric.

Its a Center 300
http://www.homershams.co.nz/i_cat_handheld_temp.htm

[Manukau heads obs]

what you have is unsheilded from radiated heat
its really only designed for inside use
outside you get reflected long range infra red radiated heat from sun reflecting off objects around you....hence a louvred shelter shades the sensor from that