The sensor instrument is an Ultimeter Weather Station 800. The Weather Station consists of a keyboard/display unit (which houses the embedded electronics), an anemometer and a temperature probe. This line of Weather Stations are professional grade weather instruments. The display unit has a serial (to USB-universal serial bus) connection to send the data to a personal computer. Shown at right is one (1) of the three (3) Ultimeter models, the 100, 800 or 2100.
The anemometer is mounted at a height of 15 feet. Anemometer has good exposure for East-Northeast winds to to South-Southwest (70° to 225°), but Westerly & North winds are blocked by trees
If you are interested in a Weather Station, the Ultimeter is available from Peet Brothers (peetbros.com). The Weather Center uses the Ultimeter 800. We would recommend the Ultimeter 2100, as it has barometric pressure and most features, while the Ultimeter 100 has just the basic wind and temperature.
The local PC software communicates with the Ultimeter 800 via the serial port. Records are continuously sent from the Weather Station to the PC. The PC analyzes the data stream and converts values for current observations. The software also calculates averages (ie: 1 minute or 5 minute) for wind speed and direction. The data is sent (via an http web request) to an Internet web server, which is running the Weather Center web application that you are currently viewing.
The Data is sent from PC to web server at 1 minute intervals at a minimum, but the update frequency increases to every 15 seconds when windy. These dynamic updates provide better data when conditions get better. Data is optionally sent to a WeatherUnderground site on the 1/4 hour, here is the link.
At the web server, the Weather Center site manages the database tables that store the recorded observations, generates the web pages and the graphs within. The site application also provides the logic for analyzing the data.
The graphs generated for the Weather Center utilize the Google Chart API. The wind speed graph is produced every 5 minutes. The other 3 graphs are produced every 15 minutes with one generated every 5 minutes. Graphs can be viewed either 'full day' (24 hour) or 'daylight' (12 hr, 8am to 8pm) for the time frame. The time the graph was generated can been seen below the graph.