South American Forecast Little Changed; All Eyes on Late December: The GFS’s high resolution 7-day forecast is below, and of note rain has been shifted southward into Buenos Aires & La Pampa late next week. This moisture will no doubt be welcomed, but it’s Central & Northern areas of Argentina that in the most needed of better rainfall. Sunday night’s forecast will be rather important, as ensemble models suggest normal Argentina rainfall beyond Dec 17-18. Whether this stays in the forecast over the weekend will be critical, but clients should pay most attention to 7- and 10-day forecasts.
Otherwise, the graphic also makes clear that additional boosts in soil moisture lie ahead for Mato Grosso, Goias and Minas Gerais, as well as fringe producing regions in far N Brazil. Precip in S Brazil and Argentina will be limited to scattered events, and as temps in Argentina rise into the 90 & low 100s, soil moisture levels will be drawn down further. La Nina forecasts suggests the phenomenon will last into the early part of spring. We’re so far unwilling to embrace a major pattern change in Argentina.
Risk of Southern Plains Drought Intact; Pattern Shift Elsewhere? The US forecast into Dec 20th is unchanged, and is still completely dry outside of the Southeast. Temps will be split noticeably, with normal/above normal temps to stay intact out West, and with deep low pressure maintaining a rather cold pattern in the east. We’ve mentioned this week that soil moisture currently is not important, but the trend is no doubt one of expanding drought into late month, particularly across the Southern Plains.
This afternoon’s January precip anomaly forecast is at left, and if verified moisture relief will develop across LA & AR beginning next month. But continued dryness will outline the US HRW Belt, and monthly winter wheat crop conditions will be of interest.