The following content was provided by meteorologist Gail Martell of MartellCropProjections.com:
Midwest Soil Temperatures Warming
A warm and sunny weekend warmed up field temperatures but field conditions are still not warm enough to plant corn. Temperatures climbed into the 70s F yesterday in the US heartland, the warmest day so far in April. Very cold conditions in March, 4.5 F below normal, caused deep soil layer freezing.
Soil temperatures presently are in the mid 40s F from Nebraska to Indiana, while fields are now mid and upper 30s F in the Upper Midwest including southern Minnesota, South Dakota, northern Iowa and Wisconsin, and 5-7 degrees warmer than last week. The germination threshold for corn seeds is 52 F. Fields are still frozen and snow covered in northern Minnesota and North Dakota into the Canadian prairies, key spring wheat growing areas.
Strong weekend warming developed from a weakening Arctic Oscillation (AO) becoming less cold than previously. A fresh cold outbreak is predicted Thursday-Friday suggesting the Arctic Oscillation is not finished. Maximum temperatures would drop back into the 40s F while freezing temperatures would develop at night 20s-low 30s F. North Dakota projected temperatures would be 12-15 F below normal. Snow has not yet melted in the top US spring wheat state and also Saskatchewan and Manitoba in the Canadian prairies.
The 6-10 day forecast indicates moderating temperatures across the heartland though the northern United States would continue cold. This is a classic Arctic Oscillation signature.
Martell: Midwest Soil Temperatures Warming
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