Brazil and (More) Europe Rains Ahead!

Fig. 1-2: The South America 7-day percent of normal rainfall and 15-day percent of normal rainfall forecast.

Discussion: The South America 7-day percent of normal rainfall observations reveal a much drier trend across Argentina while patchy heavy rain areas are developing in Brazil (Fig. 1). The 15-day percent of normal rainfall forecast across South America by ECM ENS stays wet in Brazil (Fig. 2). Curiously, the required wet support from the convection phase of the Madden Julian oscillation (MJO) remains absent in the 8-14-day period while ALL operational models are trending wetter in Brazil. One possible explanation is a resurgent MJO in the Indian Ocean (now) having a farther eastward reach as the middle third of April arrives OR a lingering influence of positive phase of the southern annular mode (+SAM) responsible for a fast-moving jet stream in the mid-altitudes sometimes able to leave upper troughs behind near Brazil.

A wet surge across Europe (motivated in-part by Madden Julian oscillation) is impressive during the past 7 days (Fig. 3). Southwest Russia managed to avoid the wet weather. The GFS 15-day percent of normal rainfall forecast (Fig. 4) remains soaking wet across most of Europe but still not reaching Southwest Russia where dry soils are accelerating.

Fig. 3-4: The Europe 7-day percent of normal rainfall and 15-day percent of normal rainfall forecast.