a daily poll of all sites. Special polls are conducted more frequently in response to specific needs. The new generation of remote sites, master stations, and central computer facilities allows for hourly interrogation of remote sites. The system has the ability to vary the configuration of a remote site by transmitting the appropriate commands telling the remote site what sensors to turn on or what parameters to send. A variety of calculations can be made on any sensor channel. For example, the user can select maximum, minimum, average, standard deviation, or circular averaging. Each sensor can be accessed independently at a specific interval. For example, wind speed may be sensed every minute during the day to arrive at an average, while the snow pillow may be accessed every 15 minutes for the accumulated total. System performance has increased over the years, mainly due to a better understanding of meteor burst communication characteristics and improved equipment. While a 95 percent response to a system-wide poll is the standard, over 99 percent is common. Data storage, management and accessibility All data are received by the SNOTEL central computer, which in turn is linked to the Centralized Forecasting System (CFS) in the NWCC where data can be accessed. Once on the CFS the data is kept in a relational database, where various analysis and graphics programs are available. Current and historical data and analyses are available by dialing into the CFS, by disk or tape media, paper copy, and on the Internet. References External links Official SNOTEL site Meteor Communications Corporation What You Don’t Know About Snow: The USDA’s SNOTEL Network is Playing a Critical Role in Protecting Water Resources in the Western United States Meteorological stations United States Department of Agriculture Snow