The strongest marine heat waves (MHW) on record in the West Pacific and in-between Japan and the Asia Coast extending to MHW’s NEP25A and NEP25B in the Northeast Pacific are well-correlated to the summer 2025 upper air pattern featuring a strong upper-level high-pressure ridge. Similarly, the MHW’s in the east/northeast portion of the North Atlantic are well-correlated to a semi-permanent upper-level high-pressure ridge dominating the west/south portion of Europe during summer 2025.

The lack of tropical cyclone activity across the Gulf of Mexico and Caribbean Sea is allowing each basin to shift warmer. The Gulf of Mexico is nearly 1C warmer than normal and warmer by 1/3C during the past 30 days. The Caribbean Sea has warmed by 2/10C during the past 30 days to 0.65C. However, the North Atlantic basin is marginally warm at +0.34C and much cooler than 1 year ago by 0.52C.

The Climate Impact Company constructed analog climate outlooks for meteorological spring 2025 and winter 2025-26 is issued. The spring season is mostly cooler than normal across much of the continent with a wet bias in the East. The summer outlook reverses drier and hotter in the East.

Intense heat will spread across much of California during the next few days leading to the hottest summer 2025 event of the season. Sacramento and Burbank reach 102F THU/FRI; San Jose to 95F tomorrow; Bakersfield 108F on Friday. Farther east, Las Vegas reaches 110F and Phoenix 112F on Thursday.