05/31/2024, 8:08 am EDT
A persistent marine heatwave in the mid-latitude West Pacific has elevated high pressure aloft risk for much of the past several years. A strong marine heatwave in the Northeast Pacific in 2014-16 having tendency to re-emerge in that area last decade shifted westward toward the China Coast and eastward to the Dateline in this decade. The marine heat wave is vividly evident east of China and Japan now and aloft is well-correlated to strong high-pressure ridging extending across the mid-latitude West Pacific to Mongolia during the past 45 days.