For example, Iowa had 3.2 fewer days over the past week to plant corn, and as a result is nine percent behind last year's pace and two percent below the five-year average.
Vietnam produced just 147,500 tons of soybeans in 2016, up 0.8 percent from the previous year thanks to higher yields, even though the total acreage shrunk almost 7 percent in the same period to 94,000 hectares, government statistics showed.
USA wheat futures slipped on Thursday, hovering near a 2-1/2-week low hit in the previous session, on plentiful global supply, while corn and soybeans were largely steady.
Similar to the market lows last fall which came ahead of a big USA crop, the market may have already "priced-in" a big South American crop, Suderman said. Nationally, corn planting was six percent complete as of April 16, 2017. In northwest, west-central and central Iowa, farmers have planted over half of their expected oat acreage. IL at six percent is half the average and Missouri has only 17 percent of the crop planted compared to the average of 25 percent and last year's record progress at this time when over half of the crop was already in the ground.
Spring wheat is similarly behind, with 13% planted versus 21% for the 5-year average.
Last year, more than half of Vietnam's soybean imports came from the US, followed by Brazil, Canada, Argentina and Paraguay, the report said.More news: Violence spikes in Kashmir after videos inflame tension
The June report tends to capture the soybean upside well when corn planting is slow. "We've had a consistent rain and cloudiness for over two weeks". In recent years, we've seen growers respond quickly to planting delays by increasing productivity later in the planting season.
Weather forecasters are looking at drier weather at the end of April or start of May in the U.S. Midwest which should allow farmers to make better progress with fieldwork, Commonwealth Bank of Australia analyst Tobin Gorey said in a note.
Brazil's soybean inventories are projected at 22.6 million tons from 18.1 million a year earlier, according to the USDA.
Even so, weather will remain a key driver of market uncertainty, Newton adds.
Topsoil moisture levels rated zero percent very short, one percent short, 74 percent adequate, and 25 percent surplus.
Last year, competition for soybean exports from South America slowed into the summer months due to a short crop in Argentina, but the size of the crop suggests that won't be the case this year, Suderman said.