Information about the donors was included on a plaque added to the sculpture's stem in the weeks following the dedication. Each day at noon, the columnar machine performs a two-minute sequence that begins with a trumpet fanfare of the opening bars of Aaron Copland's "Fanfare for the Common Man", and produces mist and flashing lights. It eventually reveals one of three metal symbols: a stylized golden sun ("helia") for clear and sunny weather, a blue heron (Portland's official bird) for drizzle and transitional weather, or mist and a "fierce, open-mouthed" dragon for heavy rain or stormy weather. The fanciful symbols change at the same time every day, representing weather predictions for the following 24-hour period. "Helia", described as "gleaming", was designed by Jere Grimm; her design would later be applied to one of her husband's pots, exhibited in 1989. The trumpets are allowed to play at noon due to a waiver of Portland's noise ordinance for that time period. Ray Grimm constructed the blue heron symbol, and the group collaborated on the dragon symbol based on his drawings. In order for the machine to display an accurate weather prediction, as reported by "The Oregonian" in 1988, employees of Pioneer Courthouse Square contact the National Weather Service each morning at 10:30 a.m. for the forecast, and then enter information into the machine's computer, located behind a nearby door. The machine, whose height is reported to be between , includes two bronze wind scoops that turn in opposite directions. It also indicates the temperature (when or above) via vertical colored lights along the sculpture's stem. Measured by an internal gauge, the machine displays blue lights for temperatures below freezing, white lights for above freezing and red lights to mark every ten degrees (°F). Referring to an additional light system (below the stainless steel globe) that indicates air quality, "The Oregonian" reported in 1988 that a green light indicates good air quality, amber reflects "semismoggy" air and a red light indicates poor air quality. However, in 1998, one writer for "The Oregonian" warned: "you don't want to breathe so much when the white light is on". Pioneer Courthouse Square employees enter air quality information into the machine's computer following routine checks with the Department of Environmental Quality. In addition to its pre-dawn dedication on national television, "Weather Machine" had a public dedication at noon on August 24, attended by Mayor Bud Clark and other city officials.