The forecast for the next two weeks is largely devoid of heat but is also lacking rainfall, which is not viewed favorably by the market as many areas of the Corn Belt have had below-normal precipitation in recent weeks.
But without a significant heat event in the forecast through the first three weeks of July, when corn is pollinating, national corn yield is unlikely to fall too far below the long-term trend - despite the expected dryness.
Most of the US Corn Belt has not dealt with unseasonable heat since the first half of June and notably cooler temperatures have prevailed ever since. Weather forecasts as of Wednesday call for the continuation of average-to-cooler conditions for the next two weeks - but without abundant rainfall.
The situation in the Dakotas is different, though, as farmers there are dealing with a significant drought that has been laced with frequent bouts of extreme heat. And unfortunately, considerable relief may not be on its way anytime soon.
Some weather forecasters have been calling for widespread heat to return - and possibly stick around - at some point this month. But weather models have not yet validated the forecasters since the heat has remained on the western fringe of the Corn Belt, and Chicago corn futures have struggled to move much higher as a result.
HOW FAR BELOW?
Assuming that for the next month or two significant heat remains largely absent from the core Corn Belt - which extends roughly from the Dakotas in the west to Ohio in the east - national yield in the vicinity of 167 or 168 bushels per acre is plausible even if it remains dry.
Final corn yield has fallen below the US Department of Agriculture's initial trend yield 10 times since 1993. July and August temperatures were average or below average in only three of those years, one being 1993, which is among the country's worst corn harvests.
Further investigation and some hindsight re-evaluation of USDA's past trend yields would suggest that given the state of the 2017 corn crop and the weather forecasts as of early July, final yield would be unlikely to fall more than 3 or 4 percentage points below USDA's trend of 170.7 bpa - everything else being equal.
A loss of 4 percent would place 2017 yield at 164 bpa, well off last year's record of 174.6 bpa, though the comfortable domestic carryout levels north of 2 billion bushels would certainly limit the impact of a lower yield.
But a yield in the mid-160 bpa range would surely cut down on the new-crop carryout and place just a little more pressure on the 2018 harvest to perform in order for the stocks to avoid being pared down even further.
2017 WILD CARDS
North and South Dakota have undoubtedly drawn the short straw this year in terms of weather, and national yield could be further affected based on how far the Northern Plains crop falls.
South Dakota grows 6 percent of the US corn crop and North Dakota accounts for just over 3 percent. South Dakota corn yields typically come in around 9 percent below the national figure while yields in North Dakota land closer to 20 percent below.
Aside from the hot and dry forecast that continues to plague the Dakotas, the soil moisture situation is already fairly dire. North Dakota soils are among the driest since August 2008 and South Dakota has not been this dry since May 2013. A freeze event also moved through late in June, piling on the problems for the young corn.
As of July 2, some 42 percent of the South Dakota corn crop was rated in good or excellent condition. In North Dakota, it was 55 percent, well below the national rating of 68 percent.
Another unknown right now is in the Eastern Corn Belt, where good-to-excellent ratings have been well below previous years from the start.
Indiana in particular - which grows 7 percent of the national crop - has had particularly low ratings despite having what has seemed like decent weather. Some 47 percent of the Indiana corn is in good or excellent condition, up slightly from 46 percent in the week prior. Ratings have climbed more notably in No. 2 Illinois and Ohio, but are still below last year's levels.
Many farmers in Illinois have wanted a good rain for a while now. Showers and storms have been moving through the state over the past several weeks, but the sporadic and localized nature of the events means that while some growers have finally received the needed relief, a lot of others have not been so lucky.
The issue of variable rainfall has also prevailed in parts of the Western Belt, as June precipitation fell short of normal in many spots across top grower Iowa.