Another hot week across the western US; heat to build into Canada
The heat will just not go away. After a very warm month of July and start to August for many in the West, the pattern over the next week will favor even more intense heat.
Another strong upper-level high is forecast to build over the western half of the U.S. and into western Canada through this week.
GEFS 500 mb height and anomaly
This will send surface temperatures well above-normal and in some places in the Northwest and western Canada, above records.
The largest temperature anomalies of 12 to 25 F above-normal will be found across the Northwest US and western Canada and across the Canadian Prairies. The most intense heat will occur over the second half of the week.
GEFS 2-meter temperature anomalies (C)
Some places that can break records include Spokane, Washington; Boise, Idaho; Calgary and Edmonton, Alberta. In fact, the forecast high of 98 F (37C) in Calgary on Friday would break the all-time daily high temperature record!
Afternoon temperatures in the mid- to upper 90s will continue in Los Angeles with temperatures in 100s and 110s in the valleys and deserts of Southern California over the next several days.
There will be an increased risk for heat-related illnesses. If possible, avoid being outside for extended periods of time. It is important to drink plenty of water to stay hydrated. If you are outside, wear light colored clothing and take frequent breaks. Scheduling time outdoors to the early mornings or evenings is recommended if you must be outside. Remember to frequently check on the elderly and children and don't forget about your pets!
The position of the upper-level ridge and Hurricane John moving parallel to Baja California will induce a southerly flow across the Southwest. This will help bring more monsoon moisture farther north across New Mexico, Arizona and Southern California for the second half of the week.
Thus, afternoon and evening thunderstorms will become more widespread Wednesday through Saturday, especially in the mountains. The risk for flash flooding will increase as well.
As Hurricane John churns near the western coast of Baja California, it will generate high surf and rip currents along the Southern California coast. Aside from this and late day mountain thunderstorms, no other impacts are expected.
