Over the weekend, GFS indicated potential for an emerging chilly trough across Northwest Eurasia in the 11-15-day period. Last night, ECM joined forces with GFS as forecast confidence increases dramatically. The negative phase of the Scandinavia Index supports the presence of the projected Northwest Eurasia trough by the operational models.

An upper trough located in the northwestern Gulf of Mexico spawning a massive amount of rain across the Gulf of Mexico affecting the coastal region. A careful watch late in the period for any subtropical/tropical low-pressure development.

A chilly outbreak remains in the 11-15-day forecast across Argentina into Southwest Brazil as meteorological winter 2025 arrives. There is marginal <32F/<0C risk in northeast Argentina with the season's first cool burst. The intensity of this potential event may be a guide on additional cold risk as wintertime arrives in South America.

Unusually cool weather across the East U.S. the last third of May but warmer changes in June are forecast by ECMWF including robust anomalous warmth for most of the U.S. by week-4 (June 8-14). A tendency for wet weather in the northwest Gulf region is likely to continue in June.