On retiring I decided, after a little while, to start taking readings of temperature and keeping a weather diary. There is so much information on the Internet that I was very loathe to do any more but fairly recently I started to think about having an automatic weather station. This obviously required a web site as well if I was to share the information. I have also recently joined COL(Climat Observers Link) and that further encouraged me to share information. Creating a web site was not an easy task to me, not being very technically minded, so I found a local company to do it for me. Well that is enough about me, so on to my site. On it you will find my own automatic weather station, in a very sheltered site, in my back garden, the photograph shows the Davis Vantage set up I have. The data is uploaded into my computer by the Davis software, and is updated every 10 minutes.You can access this current weather, by the link buttons at the top of the screen. Most weather parameters are shown down the left hand side with the valid time at the top. Graphical representations of most of these elements are shown on the right for the past 24 hours. Go to Statistics and click on weekly graphs and the past week is shown for the main elements. The history graphs are not yet the same elements as the weekly graphs. On the left I have not yet managed to get a date stamp for the maximum and minimum values for months and year. There is data supplied by the Davis system, in the form of graphs, in the STATISTICS back to when I started with it in October 2004. Another section in there is slowly being updated with my own weather diary, from now, eventually back to January 1997. Even further back, and goodness knows when it will be completed, will be data from RAF Finningley. This site has data from about 1943 up to its closure in September 1995. Its a very big task so its going to take me a long time but please browse through what I have available. On the weather sites link there are a number of sites that will open up. All are first class in my opinion, some give actual weather, radar pictures, satellite views, some give simple forecasts, others are for the more knowledgeable with links into centres that produce ‘model’ output forecasts. Thank you for visiting my weather site, I hope you have enjoyed it. Please e mail any comments you may have to me at the Contact Me button at the bottom of this page. Updates and changes below: Notes on my observing site and readings after 17 years with various types. The first thing to comment on is that the observations are from my back garden, roughly 10m square facing due west. Trees obstruct the bottom of the garden but do not cast a shadow over the Davis observing site. There is a brick wall to the north, next doors garage and a 6 ft high fence to the east with the back of the house some 12 metres or so north of the site. The reports available on line from my web site, usually 24x7 every 10 minutes supplemented by my own input monthly in a weather diary. This is almost a carbon copy of the type used in the UK Met Office, recording times and types, intensity of precipitation, gales, frost, snowfall etc again available on my web site under statistics or Summary. www.johnholmes-weather.co.uk Rainfall is well below other sites in the area, I would estimate that totals, daily, and monthly are some 25% too low. In high rainfall occurrences they seem to be slightly less than this value. My wind speed is obviously well below that of more exposed sites but is perhaps fairly indicative of similar sheltered urban locations in the area. Gusts are often less than 10% below the open site at Doncaster airport. Mean speeds are well below from most directions. Temperatures are the item that I have spent most time and effort in attempting to get representative readings. When I worked at RAF Finningley (now Doncaster airport) the readings there were for a class I full synoptic Met Office site. My original mercury thermometer, maximum and minimum were ‘old’ Met Office stock and calibrated by the National Physics Laboratory as were all Met office thermometers. Over a two year period my temperatures were within 0.3C of maximum and minimum values when compared to Finningley. When they were replaced by a digital maximum and minimum direct readout thermometers they too were no more than 0.2C outside the previous ones over a 12 month period. In the end I accepted the minimum values and felt that 0.5C needed adding to the maximum value in most instances. In 2004 I started to use a Davis Vantage wireless system coupled in to my recently built web site. Again most of the time its values appeared, comparing to the previous thermometer system, to be giving values about the same at maximum and minimum readings. There was an error, in spring mainly, with values soon after sunrise until about late morning with sunshine on the equipment in spite of shielding that gave readings that were too high. However it did not affect the highest and lowest values. Recently, over the past 12 months I have been doing some comparisons with other amateur weather stations close by me. They range from 1.5 miles to 3.5 miles away and, from looking at their exposures, to have fairly similar exposure to me although in general they are less surrounded by items mentioned in my first paragraph. Overall I appear to be showing values at maximum and minimum to be 0.5C possibly 0.75C higher than these 3 sites. As a result of this I, 2 years ago, I dropped the 0.5C correction to the maximum. Since then my maximum values do appear to be within tolerance very similar to the other sites. However, looking at my minimum readings, and the number of air frosts reported, it seems that my minimum readings show about 0.5C too high. As of 1 March 2013 my readings will therefore be reduced by 0.5C for minimum values ONLY. John Holmes 28 February 2013 |
