Heat Inches Eastward; Crop Benefit Only Regional Near Term: There’s still no sign of a major pattern shift as a strong high pressure Ridge looks to dominate the North American weather pattern through the final week of July. The midday GFS even pushed the Ridge eastward into the heart of the Corn Belt in the 8-15 day period. The major forecast models are in general agreement that as soils dry across the Western Midwest, excessive heat will inch into MO, IA and MN beginning next week. The outlook remains concerning for crops.
In the nearby, lite to moderate rainfall will ride along the northern edge of the high pressure Ridge. 7-day accumulation is at left, and pockets of the Eastern Corn Belt will benefit from coming moisture and near normal temps. However, follow up showers are not indicated, and as corn’s moisture demands peak in the next 2-3 weeks, a steady stream of moisture (1-2” per week) is needed to stem further yield losses.
And even coming rainfall won’t contribute to moisture reserves. The GFS’s precip forecast implies ongoing draws in soil moisture loss through the next 7 days, with the bulk of change projected across IA, MO and S IL.
Beginning early next week, the high pressure Ridge moves eastward, with its mean position July 19-23 to be located direction aloft IA, IL and IN. High temps in the 90s and low 100s will be ongoing across the Western Plains. Readings in the low/mid-90s will be established across the W Corn Belt, including IA, MO and S IL. Very little precip is forecast beyond the next 3-4 days.
And so the theme is that of expanding drought and abnormal dryness into the Plains and W Midwest, along with a rise in temps through the balance of the month. The timing of this heat expansion is critical. Nationwide, the corn crop will reach 50% silking in the next 7-10 days. Moisture needed to ease drought conditions out West ranges from 6-10”, which will take time to erase.