About

Smith Mountain Lake Weather

This website is intended primarily to provide weather information for residents of and visitors to the Smith Mountain Lake area. The equipment used is the best of the Hobby Grade available and is maintained to high standards both by calibrating against stand alone instruments and comparing to national networks via the internet. At this time we have no intention of providing weather information related to forecasts* but rather what the weather is and what it has been. We also have two web cams available so you can "look out the window" to confirm the instrument readings.

Our weather equipment consists of a Davis Vantage Pro 2 wireless instrument package, initially installed 06/20/06, located within twenty five feet of the shore of Smith Mountain Lake. The barometric pressure is read at the Davis console located in our weather office. In as much as barometric pressure is relative to ones elevation above sea level, our location on the shore of an Army Corp of Engineers controlled lake, allows us to determine our elevation within inches rather than a GPS determined elevation. We also have a Boltek Lightning detection antenna mounted above our roof line at an elevation of approximately fifty feet above SML. The webcams are a Logitec 9000 pro located in the office and looking out a SouthEast facing window, and a Vivotek PZ6112 Pan/Tilt/Zoom network camera in a weather proof housing mounted high on the SE side of our home. The Vivotek can be controlled by guests. In January 2012, we added a Davis 6372 Wireless Temperature Station to incorporate the lake water temperature in our data.

The information from this array of instruments is collected on a specially built computer powered by a Intel Pentium E2180 @ 2000 MHz processor w/ 2 GB DDR2-SDRAM. The information is passed from the VP2 wirelessly to the Davis Console in our office and from the console to the computer via a serial connection. The information is then processed by various software programs and dissiminated to various locations within my home and onto the internet via a DSL connection.

We have many instrument used to calibrate our Davis VP2 including a Taylor Instrument Company Sling Psychrometer, an Industrial Instruments & Supplies Psychro-Dyne ( a battery powered sling psychrometer), and a couple of digital sling psychrometers. The tipping bucket rain gage is calibrated with a manual 4" rain gage and a Torent 3 1/2" electronic gage. I have a hand held Davis "Turbo Meter" electronic wind speed indicator to confirm wind speed reports but I haven't figured how to get a ladder to the anemometer which is approximately thirty five feet above lake level.

The Software used is anchored by a suite from SoftWx (http://www.softwx.com). "StartWatch" starts all of my weather programs and watches over them. If any of the programs falter, StartWatch restarts it. VirtualVP is a com port sharing program which allow multiple weather programs to function. VPLive is a program that displays the information received from the Davis console and send the proper barometric pressure information to CWOP ( http://www.findu.com/cgi-bin/find.cgi?call=CW6097) at the proper interval. Virtual Weather Station is a graphically intense weather program by Ambient Weather (http://www.ambientweather.com/) that compiles many data points from the Davis feed to allow users to see what the weather is doing. I FTP my information from VWS to my website and other sites I support with FLING, a free FTP program (http://www.nchsoftware.com/ftp/index.html ). We use Cumulus, a very nice software package, from http://sandaysoft.com/. We are also running WeatherLink 5.8.1, a program provided by Davis (http://www.davisnet.com/weather/) with the DataLogger. Lightning 2000 by Aninoquisi (http://www.aninoquisi.com/) is the interface with the Boltek Lightning Detector (http://www.boltek.com/default.html) system. Up to the minute area wide lightning data from Lightning 2000 is available by clicking "SML-Lightning" in the left hand column of the home page. The L2K script is the work of Tom of Matangi Weather, Matangi, Hamilton, Waikato, New Zealand. ImageSalsa (http://www.imagesalsa.com/) is used to process the camera feed from the Logitec 9000 webcam. The HISTORY of this site has been recorded by WeatherUnderground and is available on site by "PHP Wunderground Station History Script". I wish to thank Jim McMury of Juneau County Weather (http://www.jcweather.us/) for the script. Finally, the software used to control the Vivotek PTZ camera is a "roll-your-own" that started with my concept and implemented with URL Commands of the network camera and much help from friends in WXForum.net (http://www.wxforum.net/index.php).

* This "About" page was originally written in 2009. I have recently (2011) decided to make a best attempt at a localized forecast. To this end I have added Tom Ehrensperger's Wxsim which integrates NWS regional information with the local Davis VP2 weather station for a customized local forecast. This information is accessed by clicking "SML Wxsim Forecast" in the left hand column of the home page. This wonderful display is a script by Henkka of Weatherstation Salo, Pertteli, FI, with help from Sante of Maceratameteo, IT, Tom Stolze of Ofallonweather, Ofallon, MO, and Jack Ahern of Branford Weather, Branford, CT.