California’s already severe wildfire season likely to worsen as no relief is in sight
By Alex Sosnowski, AccuWeather senior meteorologist
August 12, 2018 - 9:32:15 AM EDT
Any hope of lasting relief from fire weather by way of rain and lower temperatures is months away for much of California.
The two key ingredients for fire weather in California, heat and dryness, will continue in the weeks ahead.
Weather pattern to stay locked in for the long haul
Other than a fluctuating sea breeze along the California coast that may alter temperature and humidity levels a bit, people in the region should not expect any blasts of cool air or widespread drenching rainfall any time soon in the southwestern corner of the nation.
The marine flow may cut temperatures and raise humidity levels in coastal areas periodically, including this weekend, but these conditions will not penetrate very far inland or last for very long.
What is needed is a large sweep of cool air with drenching rainfall but without strong winds. However, this is neither the time of the year to expect such conditions, nor are these conditions forecast for many weeks.
"There are no reasons to expect a major pattern change in the weeks ahead," according to AccuWeather Senior Long-Range Meteorologist Jack Boston.
Boston expects a northward bulge in the jet stream and an area of high pressure to hold over much of the West through at least this month.
While an El Niño may develop this autumn and last into the winter, the winter storm season and the potential for drenching rainfall and heavy mountain snow are months away.
"As we have seen before, El Niño is no guarantee of sustained rainfall and a lasting end to the drought in California, since there are many other factors to consider," according to AccuWeather Lead Long-Range Meteorologist Paul Pastelok.
"There is a chance that parts of Northern California are able to get into some consistently wet weather late in October and November, but we just don't see any significant rain coming to Southern California through at least early December," Pastelok said.
The only way that parts of Southern California might get brief rainfall over the next few months is from a renegade tropical storm in the eastern Pacific that pulls moisture northwestward from Mexico.
"Relief from a tropical system tracking nearby is a long shot, at best, for California," Pastelok said.
While a few rogue thunderstorms may wander westward into parts of western Arizona, southern Nevada and California once in a while, they will not be the type of storms that bring substantial relief or a change in the weather pattern.
Rainfall with the monsoon-based storms will be highly localized. The storms are likely to be so isolated that the vast majority of the region will not get a drop of rain over the next few weeks.
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Lightning strikes and gusty winds surrounding the narrow patch of thunderstorm rainfall could make matters worse for wildfire ignition and firefighting efforts.
Not the worst year for fires, yet
The overall trend of acreage burned in the United States since the early 1990s is up.
The acreage of burned areas in the western United States so far this year is also above the 10-year average, according to the National Interagency Fire Center.
For the year to date, 5.4 million acres have been charred, compared to the average of 4.2 million acres.
Last year ranks as the worst on record with more than 10 million acres burned from Jan. 1 to Dec. 31. With many more weeks of fire weather in store, the acres burned will continue to increase.
As of Aug. 10, the active fires in California have been deadly with 10 people losing their lives. The Carr Fire has claimed the lives of eight people, while the Ferguson Fire has killed two.
The Mendocino Complex, Carr, Ferguson and Holy fires in California alone have burned more than 600,000 acres.
The Holy Fire is among the newest large fires to break onto the scene and is affecting heavily populated areas of Orange and Riverside counties in Southern California. At least 10 communities in the path of the blaze have been given mandatory evacuation orders, and nearly 3,000 structures near Lake Elsinore remain threatened.
California Gov. Jerry Brown declared a state of emergency in the two counties due to the Holy Fire.
As large as the fires are, many communities will not be directly affected by the blazes. However, little movement of air will cause smoke to collect in the lower part of the atmosphere.
The smoke has been and will continue to be a problem over a large part of the western U.S. through the rest of the summer.