MT. JULIET, Tenn. (DTN) -- Gro Intelligence's national average corn yield has climbed from 177 bushels per acre (bpa) during the DTN Digital Yield Tour in early August to 182 bpa on the eve of USDA's September Crop Production report, the first to incorporate field-level data.

Gro's soybean yield estimate is also higher, sitting at 51.6 bpa on Sept. 11, 2023. It was 51 bpa during the DTN Digital Yield Tour.

Gro Intelligence Senior Analyst Will Osnato said the corn yield estimate has stayed in the 180- to 182-bpa range for most of the last month.

"This is around the time our yield model levels out," he said, adding that Monday's USDA Crop Progress report and the incorporation of the next normalized difference vegetative index, more commonly referred to as the NDVI, could shift the yield estimates lower. There's more potential for the soybean estimate to drop than corn given the plant's reliance on August rainfall, but he thinks it'd only be about 0.5 bpa at most.

Gro Intelligence's yield estimates are above the range of expectations for Wednesday's USDA report. Dow Jones reports that analysts anticipate a national average corn yield of 173.3 bpa, with all the estimates falling in a range of 171 bpa to 175 bpa.

On soybeans, analysts expect USDA to peg yield between 49 and 51 bpa.

Osnato said he expects Gro's number will remain on the high side until USDA reports its final yield estimates in January. Gro finalizes its annual estimates much sooner, in mid-October.

He said he understands why most market watchers anticipate yield cuts in USDA's next report given recent downgrades in crop conditions following late August's hot and dry conditions across much of the Corn Belt.

DTN Lead Analyst Todd Hultman said Gro's estimates are at odds with the conversation that unfolded on Twitter and at farm shows over the past month, with farmers sharing pictures of crops stressed by the heat.

"Given the late hit of hot and dry weather to this year's corn and soybean crops, it appears to me Gro's corn yield estimate of 182 bushels per acre and soybean yield estimate of 51.6 bushels per acre will prove too high," Hultman said. "I understand the improvements from rain in July and early August were very helpful for the revival of this year's crops, but many boots-on-the-ground reports of crop stress make me believe actual yields will be lower."

Osnato shares Hultman's surprise about the model's comparative resilience, adding that while land surface temperatures spiked in August, they returned to normal quickly. He also pointed to this year's NDVI, one of the model's primary data sources. NDVI measures the color of a crop from satellites and compares it to 20 years of historical data. Generally, a greener map reflects a healthier, and therefore higher-yielding, crop.

In June, the NDVI fell to one of the lowest levels since 2012. Then, July's above-average precipitation pushed it to a record high. It then stayed near record levels for much of August. It's only recently begun to decline, now pulling around the middle of the pack compared to the past 20 years.

"Relative to other years, it (NDVI) looks like it has gone down a bit, but the model is really ranking these numbers, and this last data point is just a lot less important than the ones seen in August," Osnato said. "Drought is creeping back up, but the model doesn't think it's that important at this time of the season."

There's still time left for soybeans to reflect the downgrade in soil moisture, he said, adding that the yield estimate has been ticking lower in recent days and could drop more when the next NDVI is incorporated.

"This will be an interesting lesson if something about this year is throwing off the NDVI," like the crop's rapid growth after July's rainfall. "Was that enough to sustain the crop? Because if you look at accumulated precipitation in August, it almost looks as bad as June in certain areas as far as how much below normal it was."

Hultman said there's still a chance USDA could surprise with higher-than-expected yield estimates in its Crop Production report. "I still have a lot of respect for the work Gro does. As we look back, I think we'll find that this was a highly unusual year in which the big swings in crop conditions did not cooperate well with typical seasonal trends."

The DTN Digital Yield Tour, which was conducted Aug. 7-11, paired Gro Intelligence's corn and soybean yield models with insights from farmers, agronomists and other experts to paint a detailed picture of the crops across the 10 largest corn- and soybean-growing states. You can find the collection of DTN reporting on the Digital Yield Tour here: https://spotlights.dtnpf.com/….

Katie Dehlinger can be reached at katie.dehlinger@dtn.com

Follow her on X, formerly known as Twitter, at @KatieD_DTN

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