A warm mid-winter pattern across South America this year thanks to an amplified upper-level ridge centered just-off the North Coast of Chile and inspired by aggressive anomalous warmth of the northeast South Pacific Ocean off the South America Coast and vigorous El Nino warming of the eastern tropical Pacific.

The Nino34 SSTA warmed to +1.2C last week as oceanic El Nino strengthens to moderate intensity. The ENSO climate budged toward El Nino in July as supported by a 2-to-3-week period of a negative southern oscillation index (-SOI) although SOI has shifted into weak positive phase the past 2 days.

In 10-15 days, possible changes are looming. The global atmospheric angular momentum (GLAAM) pattern may flip negative for the first time during the summer season signaling a slowdown in the upper air pattern. If so, recent much warmer GFS 11-15-day forecasts and the ECM 16-20/16-30-day forecasts may regenerate another fierce hot upper ridge pattern for mid-to-late August.

Yesterday’s rainfall needed to neutralize dry Palmer Drought Severity Index (PDSI) analysis from NOAA/CPC revealed the Midwest U.S. Drought worsened last week. Short-term forecasts indicate searing heat risk increase and limited rainfall ahead into next week as the drought will continue to worsen.