Data from the USDA's September crop report will dominate trading action today for the corn and soybean markets, but before Thursday we will likely see the focus shift towards the potential for frost in parts of the Midwest.

There is no question in my mind that we will end the growing season in parts of the Midwest on Thursday morning; the question right now is determining exactly how cold it will get and how extensive the area of sub-32 degree lows will be.

There will be scattered areas of North Dakota and northern Minnesota (as well as a lot of the eastern Canadian prairie growing area) that see temperatures to 32 degrees or lower already by Wednesday morning. On Thursday morning, I would look for lows of 32 degrees or lower for the far eastern Dakotas, far northern Iowa, western Wisconsin, and just about anywhere in Minnesota with some places getting to the upper 20s. A few scattered locations in Michigan and Wisconsin may reach 32 or a little lower on Friday morning as well.

 With NONE of the Minnesota soybean crop dropping leaves as of September 4 and with only four percent of the Minnesota corn crop mature at that time, it looks like that cold will cause damage (at least in quality if not quantity) to the crop in that state.

 The other big weather story right is improvement in the rainfall outlook for the southern Plains. Some light rains may be get started there late tomorrow night, and that will start a period of off-and-on rains for that area that could last through Tuesday of next week.

On any given day in that period, rainfall amounts and coverage may not be all that great, but the duration of the rainfall event means that most of the winter wheat area from Kansas west and south will see over 0.75" by the time we get to next Tuesday and localized rains may exceed 1.75". Better rains may also fall in the Midwest for next Monday/Tuesday after very limited rains fall this week. For both areas though this rain does not look to be any sort of start to a wetter weather pattern overall for the second half of this month.

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