Corn harvest continues at a speed now 3 times the normal clip after a week that saw U.S. soybean harvest progress more than double, according to Monday's USDA-NASS Crop Progress report.

More than 1/3 of the nation's corn is in the bin; as of Sunday, 39% is harvested nationwide, with several states -- including Illinois -- surging past the halfway point. Other key states like Iowa, Nebraska, Minnesota and Missouri saw double-digit harvest gains in the last week, while farmers in states like Indiana and Ohio remain on a slower track, with those states at 26% and 8% finished with corn harvest, respectively.

A week ago, 10% of the U.S. soybean crop was out of the field. Now, that's ballooned to 22%, according to Monday's report, with farmers in Iowa almost 1/4 of the way through harvest.

Crop yields remain all over the board in reports from around the nation's center; there has literally been a 300-bushel difference in yield potential per acre in parts of the Corn Belt. "I'm in Nebraska and yields where water was applied should be better than average, around 225 to 250 bushels/acre.

Dryland is about 0 to 50 bushels/acre," says Agriculture.com Marketing Talk visitor anthonykreifels. "Zero to 300 [bushels/acre] is the yield variation from 1 end of the field to the other."

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Moving forward, harvest will likely continue at its swift pace, now accelerated by weekend temperatures that dipped below the freezing mark in parts of the Corn Belt, according to Freese-Notis Weather, Inc., ag meteorologist Craig Solberg.

"It is believed that this freeze had no impact on final production numbers for corn and soybeans, despite the fact that such temperatures occurred close to a week earlier than normal for a number of areas (and were cold enough for a few record lows to be scored)," he says. "Many believe that it will actually be helpful for harvesting, as it will kill weeds and force corn and soybean crops to mature and drydown faster."

But moisture-wise, the outlook's a little more 2-sided. Some areas will see greater chances of rainfall over the next few days, says MDA EarthSat Weather senior ag meteorologist Don Keeney.

"Rains are expected to build into the central and southern Midwest by Tuesday, and continue there through the end of the week. The persistent rains this week will stall corn and soybean harvesting but will improve moisture for winter wheat establishment," Keeney says. "The drier pattern in the northern Midwest this week will favor corn and soybean harvesting."