Farm show week in the heart of California’s San Joaquin Valley started off with stormy clouds overhead.

However, the light rain and blustery cold wind did not seem to dampen the spirits of farmers, exhibitors and the 1,200 volunteers at the 45th annual World Ag Expo in Tulare, Calif.

WAE opened Tuesday for a three-day run as the world’s largest agricultural expo.

Patty Colson, this year’s World Ag Expo chairman, said the 2.6 million square feet of show grounds are packed with 1,471 exhibitors.

“We sold out before Christmas year,” she said. In recent years with a sagging ag economy, show organizers were selling booth space right up to show time.

Not for the 2012 Expo. Jerry Sinift, International Agri-Center CEO, said they shoehorned in some new exhibitors by surveying existing exhibitors to see if they were willing to give up parts of their spaces. “We picked up new booth space by doing that.”

The early show sell-out is due to farmers and ranchers logging one of their best years in recent times in 2011.

Mark Watte, former show chairman and a second-generation Tulare County producer, said he and his brother Brian had a very successful 2011 across the board in their row crops, dairy and tree crops.

They were not alone. Fellow Central Valley producers did well also, as well as their counterparts across the nation, many of whom attend World Ag Expo.

“I think this year’s sellout is indicative of a successful year in agriculture overall last season,” said Watte.

Both specialty and commodity crops did well economically last year. Beef prices are at record highs.

However, farming is never without challenges. This year in California it is water. Watte has already irrigated his wheat twice. Many years winter rainfall provides plenty of water. However, this season is becoming one of the driest on record and Watte has had to pump water early for his wheat. For the first time in history, no measurable rainfall was recorded in Fresno, Calif., for the month of December.

No one was complaining at Expo about the showers, only that the rainfall has been miniscule through Monday. More rain was forecast for Thursday, the last day of the three-day run.

“Another big issue facing the Central Valley is a significant drop in dairy prices over the past couple of weeks. Watte said this, coupled with the high price of feed, is his biggest business challenge right now.

In the big picture, many are saying that a solid 2011 economically is just the beginning as the world’s growing population becomes hungrier as agricultural resources shrink.