The 7-day percent of normal rainfall observations identify the expected eastward shift of patchy rainfall across parts of Argentina and Brazil. This weekend and early next week, an upper trough spawns heavy rain in East Brazil as the forecast shifts much wetter.

The 30-day percent of normal rainfall observations identify a steady very dry signature centered on Uruguay and vicinity with a patchy wet bias across west and south portions of Argentina plus East Brazil. The 7-day observations are drier except wetter Central Argentina, Northeast Brazil, and parts of Brazil due east of Paraguay.

January 2026 ranked 24th warmest of the 132-year history across the U.S. The month was characterized by prohibitive warmth for much of the month followed by an arctic outbreak later in the month across the East. Despite the chill, Eastern States managed only top 25% coldest January (at best).

Dramatic storm tracks are almost always associated with influence of the Madden Julian oscillation (MJO). The intense Southwest/South Europe storm track of the past 2-3 weeks is directly related to an eastward shift of the MJO across the equatorial East Pacific to tropical Africa.