Stevenson Weather Data
The Stevenson screen is an enclosure for meteorological equipment invented by Thomas Stevenson. Over the years they have been modified to improve the reliability of the measurements taken within. There have been several different Stevenson screens at the site over the years. At one time there were even two, one of which housed a hydro-thermograph. As time goes on of course systems break down are too expensive to replace. This what happened to the Thermograph and the Stevenson screens since they were wooden designs fell to the elements and rotted away. You can now buy plastic ones which won't rot of course but will still eventually fall victim to the sun. Also more more modern ones have black interiors which we are told don't effect the readings.
You will find the weather averages recorded by the Stephenson screen in the tables below. The data was collected from 1955 onwards.
These includes Humidity, Maximum and Minimum temperatures, Wind speed, wind gusts, Soil Temperature, Air pressure and Rainfall. The humidity is recorded via a wet and dry bulb. Soil temperatures measured at one foot. Due to EU regulations you cannot purchase Maximum Thermometers any more due to Mercury. So far a suitable replacement hasn't been found by the companies supplying Met office equipment. I had to purchase another digital thermometer which also does Minimum and is Nist Certified.. This is very accurate more so then the Davis weather station. I recently also moved the Davis temperature and humidity sensor into the screen which means I no longer need to replace the Davis fan every year and also the batteries.
The links at the bottom of the page have all been updated. These still link into the Excel spreadsheet. However the charts have now been moved chart.js and now display properly on a mobile device. The table data has also be moved from Excel into a html page which are again more mobile friendly. New features include charts showing the cloud base height and freezing level. For the long term averages the charts allow you to also select a five year average, ten year average and a fifteen year average. Previously there was only a 5 year average. The pressure table also now shows millibars as well as inches. All the tables can selected by a drop down table or directly from the provided links. Other features added are the top ten warmest and coolest days per month, Heatwave days, Heatwave streaks, Number of heatwaves per month and heatwave events. Under the wind tables you will also find the number of calm spells in a year and Windy spells. The yearly extremes table shows you the Highest and lowest temp of the year, Highest and lowest Soil temperatures, Highest and lowest air pressure, The wettest day of the year, Highest gust of the year and highest average wind speed, Highest and lowest Humidity, High and low Cloud base and high and low freezing levels.
The Davis weather station also runs from midnight to midnight so this will show slight differences from the data measured from the Stevenson screen. Also note that digital respond quicker to temperatures changes so it's possible the Stevenson data may miss some peaks and troughs. Since I've moved to digital sensors to the Maximum and Minimum this no longer applies.
A new set of Maximum, Minimum,Dry and Wet bulbs have been bought over the last couple of years. This means the Davis Maximum isn’t been used any longer. However the values tend to match the values recorded in the Stevenson screen. This allowed me to reconstruct some of the data that was missing from the 2004 data sets due to illness.I will be slowly adding further data sets although this a time consuming business.
Stevenson Screen Data and the Monthly Summaries from the Year 1998 onwards
| Stevenson Screen Data 2000 Onwards | ||
|---|---|---|
| Year | Year | Year |
| 1994 | 2006 | charts and Summaries | 2018 | charts and Summaries |
| 1995 | 2007 | charts and Summaries | 2019 | charts and Summaries |
| 1996 | 2008 | charts and Summaries | 2020 | charts and Summaries |
| 1997 | 2009 | charts and Summaries | 2021 | charts and Summaries |
| 1998 | charts and Summaries | 2010 | charts and Summaries | 2022 | charts and Summaries |
| 1999 | charts and Summaries | 2011 | charts and Summaries | 2023 | charts and Summaries |
| 2000 | charts and Summaries | 2012 | charts and Summaries | 2024 | charts and Summaries |
| 2001 | charts and Summaries | 2013 | charts and Summaries | 2025 | charts and Summaries |
| 2002 | charts and Summaries | 2014 | charts and Summaries | 2026 | charts and Summaries |
| 2003 | charts and Summaries | 2015 | charts and Summaries | 2027 |
| 2004 | charts and Summaries | 2016 | charts and Summaries | 2028 |
| 2005 | charts and Summaries | 2017 | charts and Summaries | 2029 |
Stevenson Screen Data and the Monthly Averages from the Year 2000 Onwards
Weather Averages including Hottest, Coolest, Wettest and Driest Months 1955 Onwards. Daily Averages 1961 - 1990 and 1991 - 2020.
| Stevenson Screen Monthly Averages 1955 Onwards | ||||
|---|---|---|---|---|
| Rainfall | Temperature | Average daily Temperatures 1961 - 1990 | Average Daily Temperatures 1991 - 2020 | Winds speed and Gust |
| Rainfall | High and Low Tables | All time Average Charts | Maximum Temperature | High and Low Tables | All time Average Charts | Daily Average High 1961 - 1990 | Daily Average High 1991 - 2020 | Wind Speed | Windspeed and Gust Tables |
| Minimum Temperature | High and Low Tables | All time Average Charts | Daily Average Low 1961 - 1990 | Daily Average Low 1991 - 2020 | Gust | Windspeed and Gust Tables | |
| Average Temperature | High and Low Tables | All time Average Charts | Daily Average 1961 - 1990 | Daily Average 1991 - 2020 | ||