Re-emergence of another extreme hot weather event is forecast for this weekend in the Southwest U.S., California and the Northwest States. This time the peak heat, which could reach 120F occurs in northern California and the Interior Northwest States likely next Monday.

Tropical Disturbance 92L is forecast to become a tropical storm by tomorrow night and north-northeastward into southwest Louisiana on Saturday. Northwest Gulf of Mexico waters are 85-86F which supports a hurricane. Tropical cyclone models are projecting a moderate-strength tropical storm. However, there is potential for an over-achieving system late this week in the northwest Gulf of Mexico.

A high-pressure cell over the Southwest U.S. this week strengthens to rare 6000 DM at 500 MB propelling widespread historic heat across the Southwest U.S., California and pulsing into the Great Plains and reaching western Texas by next weekend. Searing and extremely dangerous heat is caused by this super high-pressure cell.

Between the eastern entrance to the Caribbean Sea and off the northwest coast of Africa between 5N and 23N is where the tropical North Atlantic (TNA) index is calculated. The TNA is a simple SSTA value for this region which is also known as the main development region (MDR) for North Atlantic hurricanes. In May, the TNA index declined -0.50 to -0.18, the strongest negative monthly drop in the 1950-2021 climatology.