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Setting up a personal weather station: Ambient Weather WS-1080
August 5, 2010 at 01:25
I completed the installation of my new Ambient Weather WS-1080 on Tuesday. The WS-1080 is a relatively inexpensive ($109 PC / $119 Mac OS) personal weather station (PWS). I opted for the suggested solar shield – for more accurate temperature readings – which was on sale ($19.95) with the Mac bundle. The sensors consist of a anemometer (windspeed), wind direction indicator, hygrometer (relative humidity), thermometer, barometric pressure sensor and rain gauge. The sensor array is mounted on the rooftop and communicates with the main console via a 433MHz wireless link. The console then connects via USB to my Mac Mini which is then able to transmit the weather data via the Internet.
It was fun assembling the sensor array. Despite the low price tag the instruments and sensor components seem to be well made. The optional larger solar shield was quite a bit larger than the one included with the station but it seems to be providing adequate shielding. I have used other wireless thermometers and typically they become inaccurately high when the sun shines on them. Given that this unit is usually mounted where it will be in sunlight all day, this is an important consideration.
Once I had the array fully assembled and fixed to the included mounting pole I set up the ladder for the roof summit. My roof has a particularly large sanitary stack pipe (to provide proper clearance from the skylight) so I was able to mount it nearly five feet off the roof on just the pipe alone. Others who might not have such a mast already in place will want to consider a tripod or chimney mount.
The Mac software, WeatherSnoop that Ambient included with the Mac Package was very easy to set up and it flawlessly interfaced with the USB-connected LCD console. WeatherSnoop supports two of the most popular communities of amateur weather observers: Wunderground and CWOP/APRSWXNET. Wunderground in particular does a really nice job of promoting PWS usage. By default, visitors to its site are shown data from their nearest PWS, based on ZIP code. Live data from my station is the currently the default for the 93109 ZIP code. Wunderground also makes available a comprehensive collection of historical data and charts. Wunderground also offers a free iPhone app called Wunder. The app is pretty bare-bones, but it will be of interest especially to PWS owners who want a quick way to monitor their stations. Another nice feature of Wunderground is the ability to embed an HTML “sticker” of any PWS on your home page. You will see a number of options here for my station, including a pretty comprehensive Adobe Flash console (I haven’t figured out why no rain is being reported as “-999.00 in.” in the large Flash console. This software bug was fixed in Q4 2010 with a subsequent release of WeatherSnoop.):
A few pecadillos …
- I originally installed two regular alkaline AA batteries from my battery bin in the roof-mounted array. In a little more than 24 hours the station was reporting negative temperatures online. I returned home to find that the sensor array was not communicating with the console. I suspected that the AAs were not fresh so I purchased a pack of lithium batteries as recommended by Ambient. Those setting up stations in cold weather will definitely want to opt for lithium cells as they considerably outperform alkaline in sub-freezing temperatures.
- The WS-1080 has the ability to set relative pressure in the console to compensate for the elevation of the barometric pressure sensor for installation above sea level. For my location in Santa Barbara, Calif. at approx 125 feet above sea level that works out to about 0.1 inch of mercury. For a station in Denver, that would be more like five inches! WeatherSnoop version 1.7.3, which was included in the WS-1080′s box, seemed to ignore this issue and report absolute pressure. Upgrading to WeatherSnoop 1.7.4 seems to have solved this issue by calculating the corrected pressure based on the site elevation as set in the “My Site” tab in the software.
- The rainfall indicator is reporting N/A or -999.00 depending on where you look in Wunderground. My console reads “0.0 inches.” WeatherSnoop’s documentation specifically says that “rain values are not transmitted to WeatherSnoop, even though they are shown on the console.” The documentation goes on to say, “Rain Total for Year – Obtained from the station (interpreted as total since reset).” I am not sure what that means and what the implications are. Since we won’t likely be getting rain in Southern California for at least another two to three months I guess we will have to wait and see.
If you have any questions, feel free to contact me or leave a comment below. I am still working out the kinks and learning how to best keep the station accurate and online and appreciate your feedback.
Tags: ambient weather, METAR, NOAA, pws, weather stations, wundergroud
