Most of us have seen the horrific images that are coming out of the west coast from the wild fires. Homes have burned to the ground, entire communities have been destroyed, and unfortunately multiple lives have been lost as the fires rage on.
Did you know that the weather actually has significant impact on helping to fuel and spread the flames? Local weather patterns can produce strong winds that can make containing the fires near impossible for firefighters on the ground.
These strong winds are named after the region they affect. For example the strong winds in southern California are named the Santa Ana winds after the town. This will be our focus on Weather Word of the Week.
Another example would be the Diablo winds that affect the Bay Area named after the local mountain. These winds are produced in the same way, but are located in two separate geographic areas.
Santa Ana Set-Up:
A few different factors combine to create the phenomena known as the Santa Ana winds.
- High Pressure- A strong high pressure system dives south out of Canada into the Pacific Northwest. The wind flow around a high pressure is clockwise. This drives easterly winds into portions of southern California. The stronger the high pressure the stronger the wind flow.
- A trough of lower pressure digs across the western United States providing subsidence (sinking air) on the west side of the trough.
- The easterly winds descend from the high deserts where the elevation is almost 5,000 ft down to just under 3000 ft in the foothills of the Transverse Range.
- The air warms and dries out significantly as it descends towards the mountain passes.
- The winds then squeeze through the passes of the mountains and increase in strength rapidly reaching speeds of 60-100 mph at times!
The Santa Ana winds dry out vegetation, and can enhance the wild fires. The strong winds make fighting the fires near impossible and can rapidly spread the blaze as well! This unfortunately leads to more destruction in a shorter amount of time.