There was some improvement in the US weather outlook (depending on whose interpretation you go for), keeping a lid on grain prices.
But it was not enough to exert a meaningful downwards correction.
The latest run of the GFS weather model "is indicating a significant retreat in the ridge to the southwest" and to "rain in Iowa, Illinois, Indiana, and Ohio at the weekend", according to Darrell Holaday at Country Futures.
"It is not overwhelming rainfall, but there are indications of rainfall," which is what is needed, especially for soybeans, to reduce the yield threat posed by this week's high temperatures, and a prolonged dry spell.
According to Lanworth, many Corn Belt regions are on track for August rainfall 25-50% of normal.
'Yield loss and plant stress'
CHS Hedging said that "improved rain and cooler temperatures are forecasted for after the Labor Day weekend",
But "near term, the hot and dry weather conditions continue to cause yield loss and plant stress on corn and soybeans".
And WxRisk.com flagged some rainfall reduction in the latest run of the GFS, which "takes away a big thunderstorm over north west Iowa for Saturday night", Iowa, the top corn and soybean producing state, being one area which does need rain.
"The front still has some moderate or light showers with it over the eastern portions of the western Corn Belt and much of the eastern Corn Belt, but the amounts remain quite weak - 0.10-0.65 inches with 50% coverage," the weather service said.
'Few weak showers'
Whatever, the outlook was not wet or cool enough to give bears significant purchase, especially when actual rainfall, the real determinant, was weak.
"The midday Wednesday radar shows a few weak showers and storms over central portions of South Dakota. That is the only activity over any portion of the Plains and Midwest," WxRisk.com said.
Furthermore, as a reminder of what damage had been done, Lanworth cut its forecast for the corn yield by 4.9 bushels per acre to 152.4 bushels per acre, and for soybeans by 0.8 bushels per acre to 40.8 bushels per acre.
Both figures were below the US Department of Agriculture estimates, of 154.4 bushels per acre for corn and 42.6 bushels per acre for soybeans, although of course markets have already factored in yield reductions, in the price rises on Friday and Monday.
Tighter balance sheet
For soybeans, the prospect of a smaller-than-expected crop is particularly serious, with the USDA balance sheet not containing much scope to absorb losses without implying another season in 2013-14 of tight supplies.
At face value, Lanworth's estimates imply US soybean inventories of -36m bushels at the close of next season, implying the need for rationing, ie higher prices, to make the balance sheet work.
The idea that prices are high enough to instil such rationing were eroded when the USDA unveiled the sale of 120,000 tonnes of US soybeans to China for 2013-14.
Soybeans for November added 0.2% to $13.72 ¾ a bushel.
'On the defensive'
Best-traded December corn could not match that, with a less tight balance sheet, even at a yield below the USDA forecast, and less sign of demand.
Domestically, US ethanol output fell 24,000 barrels a day last week to 820,000 barrels a day, although inventories were down too, by 232,000 barrels to 16.25m bushels.
And there are continued concerns of loss of market share in exports to Brazil, armed with a weak real and the fruits of its second harvest, the safrinha crop, which is the main source of its export supplies.
Furthermore, the US harvest is building, bringing fresh supplies, and so further improving buyers' hands.
"The advancement of the US corn harvest and cheap global offers should keep this market on the defensive in the absence of additional strength in the soybean market," Benson Quinn Commodities said.
December corn dropped 1.1% to $4.80 ¾ a bushel. The decline lifted the new crop soybean: corn ratio to 2.86: 1.
'Well above the world price'
Unsurprisingly, wheat followed corn's direction, but lagged a pace behind, as has been its habit of late, ending down 0.7% at $6.59 a bushel in Chicago for December delivery.
"Wheat remains a follower," Benson Quinn Commodities noted.
It did have some claim to independent strength, with the USDA announcing too the sale of 119,000 tonnes of US wheat to an unknown destination.
But the results of an Egyptian tender, won by Black Sea suppliers with offers of a little over $250 a tonne, questioned any ideas of strong demand for US exports.
"Once again, US wheat offers are well above the world price," Mr Holaday said (although US wheat was not actually offered at the tender).
French wheat, which the tender showed had lost competitiveness against the likes of Ukraine, underperformed in Paris, falling by 1.3% to E189.25 a tonne for November delivery.
London wheat for November dropped 1.0% to £159.60 a tonne.
Among soft commodities, a strengthening Brazilian real boded well for New York futures in those of which Brazil is a major producer, raising the value of the crops in dollar terms.
The real strengthened back to a little under R$2.32 to $1 at one point, from levels above R$2.45 last week.
Arabica coffee indeed rose, adding 1.5% to 118.45 cents a pound in New York for December delivery.
But raw sugar for October could not take such advantage, dropping 0.1% to 16.44 cents a pound, remaining under pressure from Tuesday's data showing rising Brazilian output, and playing closer to a script outlined by Macquarie.
As did cocoa, which gained 1.8% to $2,498 a tonne in New York for December delivery, supported by lingering concerns over dryness in Ivory Coast, the top producing country.