Thanks for the help. It's very much appreciated. Yeah I think I am going to try and find a pole in our shed that is the highest and right size and shift the anemometer. This is on the 'to do list'. At this stage I think I will hold on buying the wireless adpater that you suggest Leroy, despite it sounding very handy, but I am saving my money for something else as well.
Thanks for asking that question Lily and replying to it Leroy. I was also wondering if there was some sort of setting that could have been used to male the rainfall reset at 9am. But as you say, I remembered that Australia was fairly unique in regards to the 9am read time.
There is another question in regards to the rainfall tipping bucket. I think my gauge is underreading rainfall. I say this simply due to the fact that I have a manual BoM gauge that I also read from, and the manual guage is always higher. For example, my YTD reading from the manual gauge is 122.4mm, however from my Davis Automatic gauge, the YTD is only 99mm. So it is under-reading. Is this normal and is there anything I can do?? I did test it before set-up, I tipped exactly 2mm into the gauge and it read 2mm, so not sure whats going on. The placement of the gauge is clear, pretty much right next to the manual gauge.
Jake - Senior AWF Forecaster
Feel free to send me a private message if you have any questions.
I've had similar issues, Jake. My rainfall reading from the automatic gauge is often slightly below the manual one, usually about 1-ish mm though, so negligible per event (although over a year could add up to something more substantial, of course).
Yeah not sure what I can do to fix my problem. In the 24 hours to 9am this morning, my automatic gauge recorded about 45mm compared to 56.2mm from my manual gauge ??
Jake - Senior AWF Forecaster
Feel free to send me a private message if you have any questions.
Wow, that's a lot Jake. I haven't had that much of a difference (that I know of, I don't always check the manual gauge until the end of an event and sometimes it overflows).
You can usually adjust the buckets on a Davis Station which I had to do to get mine accurate (compared with an ordinary rain gauge)but keep the adjustments very small. The manual that comes with it tells how to do it.
Thanks guys. I'm just awating a reply from Leroy, and I will look into all of this a bit closer. Good thing Weatherlink allows data to be edited!! Its also good that this week will be mostly dry, so I have time to check things out and muck around, and also to raise my anemometer.
Jake - Senior AWF Forecaster
Feel free to send me a private message if you have any questions.
Hi Jake, sorry for the delay. Quite a few factors come in to rainfall differences, height above ground is critical, closer to the ground the better accuracy you will have, I won't go into disconnecting the collector from the screen and extension kits you can buy from Davis, but that is a option, maybe one day.
I have 4 gauges in the back yard, 2 nylex 1000 and the 8" manual and the automatic, one nylex on carport roof at 5mt and the other nylex at 500mm above ground, the two 8" gauges are 12" apart. The nylex at 5mt is normally 2-5mm difference from the ground level nylex and the carport still has some protection.
The two 8" gauges are very close normally within a tip due to some water remaining in the siphon and bucket areas, sometimes. The nylex 1000 gauges are a good gauge for there price, after a few mm have been recorded i have noticed the rainfall anywhere from 0.5mm-1.5mm more than 8" gauges, not much but as
people have mentioned can add up over time. I may experiment one day and place a gauge into a pit into ground with the rim of the gauge just above ground level for even grater accuracy and compare. When the vantage pro 2 is mounted on a mast and you have it mounted so the solar screen is facing north, any
rainfall coming form a southerly direction can get slightly blocked from the mast going above, which its nearly impossible to stop unless mounted at the very top of the mast, which then becomes harder to maintain regularly. You need it mounted at a height that you can maintain the station and try be in a open position
as possible. The other import thing with any rain gauge is having them level otherwise you can miss some rainfall if the wind is blowing it the other way. To achieve this its hard to use the bubble level located inside the rain collector, when you have it on the mast, as soon as you put the cone back on you cant see the
level, which has more than likely changed, so the best way is to put a spirit level on top of the rain collector cone in two directions and see what you come up with, also try to keep the mast as steady as possible to stop any movement. Before any rain event try and keep the collector cone and buckets clean with a mild
soapy solution, and avoid touching the buckets with fingers as this can put oil on and cause more tips, just clean buckets lightly and hold with two fingers lightly at the bottom of the buckets without touching the inside of the buckets. The debris screen that goes in the collector sometimes gets blowing out with gusty
winds, so what i have done in the past is put some very small drops of superglue on the for spikes and dropped it into position and that holds it, make sure there are no drips as you place it into position. With calibration it can get tricky, when comparing two gauges they have to be very close to each other, make sure
you have the 0.2mm metric adapter weight fitted to the base of the buckets which should help with accuracy. you could also experiment with a medicine cup and see how many mls it takes to tip, i know for my 8" 203cm TBRG it is around 6.5mls=0.2mm per bucket tip for that size gauge, so for the Davis its a bit
smaller, so you could try a smaller test and see when it tips. If then it needs some calibration as peter mentioned very small turn of the screw into the + range. When testing cleaning the rain gauge, unplug rain connector from sim box, otherwise you have to set rainfall and clear data from the station etc.
Allways rinse buckets and rain collector with water after cleaning with soap. Sorry to bore you with all this, have a go see what you come up with after the next rain event, and can discuss further. Good luck.
I will be testing things out and looking into the information you have provided in a lot more detail when I get back from Melbourne on Saturday. Some interest in rain next week, so I will have to be fairly quick about it.
In regards to the 0.2mm metric adapter, what does this look like ? I might have it or not. I got my station from overseas so I am not sure if I have got one included somewhere with the stuff or if I still have to go and buy it.
Jake - Senior AWF Forecaster
Feel free to send me a private message if you have any questions.
At the base of your bucket arms is a magnet, this comes out and fits in the metric adapter which is a little piece of plastic, and then goes back at the base of the bucket arms,
it adds a little bit more weight, Pages 14,15 of this pdf file will explain, otherwise check your ISS installation manual.
Thanks Leroy. I actually got the US version I think, because I am pretty sure that there is no .2mm adapter in the rain gauge when I looked. However there does appear to be an adpater with the contents, so I will install this tomorrow and then wait for rainfall. Going to be interesting.
Jake - Senior AWF Forecaster
Feel free to send me a private message if you have any questions.
I installed the .2mm adapter last week, and have been waiting for some rainfall to see if things are more accurate. Finally today we have had some showers, and it looks to have closed the gap between the manual and AWS gauges. Its recorded 6.8mm since midnight today, compared to the manuals 7.2mm or thereabouts. A lot closer than what it had been recording. I have noticed a slight lean on the pole that it is installed on today, so I will also fix this up before later next week (next bout of rain), which will most likely close the gap even more.
Jake - Senior AWF Forecaster
Feel free to send me a private message if you have any questions.
No worries Jake, also sometime you can have a little bit of rainfall that gets retained in the buckets and not quite tips, and can evaporate if no further rainfall occurs. Manual gauges are the best for the final reading, when your using the 8"manual gauges with the 0.2mm graduated cylinders.
With very heavy rainfall you can miss some water at times but they give you a reasonable figure without getting drenched at 2am in the morning Best of luck with it.
Welcome to the AWF Colin As for the iphone app, I haven't heard of one but someone more knowledgeable on here may be able to answer your question. Would be fantastic if you could put a WS on your iphone and ipad.
Ok if your still searching for a station with an iphone app. Davis weatherlink has an Iphone app that will allow you to view your stations ob's ect wherever you are. http://www.davisnet.com/weather/product ... pnum=06556" onclick="window.open(this.href);return false; but you will need all the associated gadgets and Davis products=not cheap. That's the only one that I know of but that certainly doesn't mean that there isn't more???
You're only as happy as you choose to be....I choose to be miserable!
Hi.
I just wrote a lot of questions and through some computer miss-steps it seems to either be posted or lost, was not able to add a Thanks for any Help.
Regards.
Its also good that this week will be mostly dry, so I have time to check things out and muck around, and also to raise my anemometer.
As for the iphone app, I haven't heard of one but someone more knowledgeable on here may be able to answer your question. Would be fantastic if you could put a WS on your iphone and ipad.