Warm Autumn Predicted; Drought Outlook Mixed: NOAA’s updated climate forecasts this AM included ongoing normal/above normal temps through December, and mostly dry weather across the Central US over the next 45 days. The odds of La Nina developing in late fall/winter were boosted noticeably (62%, vs. just 26% last month), and overall drought is expected to persist/expand acros the Plains. Modest drought relief is offered to the Plains and IA.
The US drought monitor this week featured class reductions in MT, ND and MN, but an expansion in abnormal dryness in MO, IA, IL, IN and MI – which provides evidence that NASSS yields are overstated. Heavy rains lie in the offing Sun-Tuesday across the Plains, but no precip of note is forecast east of the MS River. Temps into the weekend will reach as high as the upper 80s and 90s.
The return of a broad NW upper air flow will allow dry weather to return to the whole of the Central US Sep 28-Oct 5, accelerating crop maturity and harvesting.
Brazil Drier in 8-14 Day Period: The EU and GFS models have trended drier across Brazil in the extended range, and so producers there will have to wait a few more weeks before the arrival of the wet season. Soil moisture as a percent of capacity this week (top) and a year ago (bottom) is at left, and while Brazilian rainfall is highly seasonal, the 2017 season has started off abnormally parched, particularly in Mato Grosso/Goias/Bahia.
The models are virtually unchanged in their 10-day outlooks. Yet more rain is projected across N Argentina early next week. High pressure Ridging will stay anchored aloft NE Brazil into Oct 1, thereby keeping precip almost completely absent through the period.
High temps in C & N Brazil will continue in the 80s and upper 90s and dryness there will get worse before it gets better. Already farmers are seeding soybeans in dust-like conditions, and re-plant will be needed if meaningful rain fails to materialize in the next two weeks.