The most popular local event is the Central Washington State Fair (1301 S. Fair Ave., 509/248-7160, www.fairfun.com ) held in late September, which features a PRCA championship rodeo, carnival, nationally recognized musical talent, nitro-fueled demolition derby, and agricultural displays. It attracts well over 300,000 visitors each year.
The Antique Power Show (509/457-8735) on the third weekend of August features an old-time threshing bee and working displays of farm equipment at the Central Washington Agricultural Museum.
In mid-February, visit the valley for a Celebration of Chocolates and Red Wine, during which the various wineries provide chocolate sweets to match their reds.
The biggest annual wine event is the Yakima Valley Spring Barrel Tasting (800/258-7270) in late April, when the wineries pour samples of their new releases straight from the barrel and offer tours, hors d’oeuvres, and educational exhibits. All 25 wineries are open 10 a.m.–5 p.m. during this three-day event.
Dog lovers will enjoy Prosser’s  National Championship Chukar Field Trials on the last weekend in March. It attracts English pointers and shorthairs from all over the country.
The early-June Mural-in-a-Day (509/865-3262) program pits than two dozen artists against the dramatic goal of completing a wall-sized mural in just one day. This fun demonstration coincides with an arts and crafts and food fair.
Treaty Days and the All-Indian Rodeo and Pow Wow in nearby White Swan is held in early June to celebrate the signing of the Treaty of 1855. The rodeo features the Yakama Nation in a pow wow and parade.
Fort Simcoe (509/874-2372) puts on a great show in June also, complete with living history presentations, traditional tribal dance, a flag-raising ceremony, military re-enactors, antique car shows, and best of all, free cake!
The 4th of July weekend brings a frenzy of activity to Toppenish : the Pow Wow & Rodeo (509/865-5566) is an event with something for everyone—a carnival, nightly rodeos, dancing, fireworks, a Wild West parade featuring cowboys, cowgirls, and Yakama in full regalia, an antique power show, and arts and crafts booths.
The Prosser Wine & Food Fair (800/408-1517) on the second Saturday of August is the largest outdoor wine and food show in the state, attracting thousands of people for a chance to sample wine, beer, and food. The event usually sells out, so order advance tickets. It’s only open to people over age 21.
In September, the Yakima Valley  girds up to go ga-ga for the great Grandview Grape Stomp. (114 Grandridge, 509/882-2100). In the town’s grandest gala of the year, groups of three grapple to gouge grapes as in times gone by and gain some Grandview glory. And a trophy. A fee of $30 gains you general admission and covers family activities galore.
The Prosser Balloon Rally and Harvest Festival on the third weekend of September attracts balloon enthusiasts for morning launches, nighttime lighted balloons, and arts and crafts exhibits.
Late into the season, November brings Tribal Jam (509/865-2800, $25), a showplace for some of the country’s best American Indian musicians and singers. The show is held at the Heritage Theater at the Cultural Heritage Center.
The season starts to winds down with Thanksgiving in Yakima Valley Wine Country, featuring food and wine-tasting at most local wineries. This is a fine way to taste a variety of gourmet foods and to get recipe ideas.
In early December, the Country Christmas Lighted Farm Implement Parade features bulb-bedecked tractors, farm machinery, and horse-drawn carriages and wagons in one of the premier lighted parades in the northwest. Call the Sunnyside Chamber of Commerce (509/837-5939) for details.