How the Santa Ana Winds Help Wildfires Spread

The Santa Ana winds are notorious for exacerbating wildfires in southern California.

These strong winds blow warm, dry air across the region at different times of the year, but mainly occur in the late autumn. They form when a large pressure difference builds up between the Great Basin – a desert that covers most of Nevada and parts of Utah – and the coastal region around LA. This pressure gradient funnels air downhill and through the passes of the San Gabriel and San Bernardino mountains toward the Pacific. According to the NWS, the Santa Ana winds can easily exceed 40 mph.

Originating in the high desert, the air starts off cool and dry. But as it travels downslope, the air compresses and warms. In fact, it warms about 5°F for every 1000 feet it descends. This dries out the region’s vegetation, leaving it susceptible to any type of spark. The fast-moving winds then fan the flames of any wildfires that ignite.

The Santa Ana winds are named for Santa Ana Canyon in Orange County, CA.

Credit: NWS

Wildfire Outbreak in Northern California

Northern California is ablaze with wildfires.

As of Thursday, according to CalFire, 22 wildfires are burning in the Golden State. They have scorched over 190,000 acres and forced the evacuation of entire neighborhoods. Officials say at least 26 people have been killed and more than 400 are missing. In terms of property damage, they conservatively estimate that 3,500 homes and structures have been destroyed.

The smoke and ash from these fires are also causing widespread air quality issues. In the Bay Area, well outside of the burn zone, air quality reached historically poor levels this week.

These huge fires are largely the result of climate whiplash. California has distinct wet and dry seasons, but they have been extreme recently. After years of drought, this winter brought the state record amounts of precipitation that spurred explosive new plant growth. Then during the summer, which was the state’s warmest on record and unusually dry, all that vegetation turned to tinder.

Making matters worse, the region’s seasonal winds known as the Diablo Winds began blowing over the weekend. They reportedly reached speeds as high as 70mph in some areas. Blowing east to west, these winds warm from compression as they flow downslope from the mountains towards the coast and dry out vegetation even further. They also fan the flames of any fire already burning and can cause it to spread very quickly.

The Diablo Winds are essentially the same type of air current as the famous Santa Ana winds in southern California. They only really differ in location and name. The Diablo Winds are named for Mount Diablo in the East Bay area and the Santa Ana Winds are the namesake of Santa Ana Canyon in Orange County.

Wildfires are not unusual in California, but this outbreak is considered one of the worst in state history. The exact cause of the fires is still unknown.

Wildfire burns near Glen Ellen, CA. Credit: The SF Chronicle

Hot Temperatures and Strong Winds Fuel Western Wildfires

Summer is wildfire season in the American West and this year it is off to an explosive start.

As of Wednesday, according to the National Interagency Fire Center, thirty large wildfires – defined as greater than 100 acres – are burning in ten western states.  These include Alaska, Arizona, California, Idaho, New Mexico, Nevada, Oregon, Texas, Utah, and Washington.

The largest is the Brian Head Fire in southern Utah. It has burned approximately 50,000 acres and forced the evacuation of nearly 1500 people. Ignited on June 17, the massive blaze is only 10% contained.

Another hard hit state is Arizona, where six large fires are currently burning. The governor, Doug Ducey, has declared a state of emergency in Yavapai County in response to the Goodwin Fire, which has burned more than 20,000 acres near the Prescott National Forest. Local officials have ordered the full evacuation of the town of Mayer, AZ.

These huge fires are being fueled by extremely hot and dry conditions that have left the region’s vegetation susceptible to any type of spark. Just a few days ago, excessive heat advisories were in effect for a large swath of the area as temperatures soared into the triple digits. Now, high winds are fanning the flames and helping the fires to spread.

Year to date, 2.7 million acres in the US have been charred. The country’s worst wildfire season on record was 2015 when more than ten million acres burned.

Brian Head Fire, UT. Credit: Desert News

Drought Update: Summer 2016

This summer has been marked by heavy rain and even flooding in many parts of the United States.  Drought, however, continues to plague large sections of the country.

According to the latest report from the U.S. Drought Monitor, 41% of the nation is in some form of drought. Many areas in the south and northeast are listed as abnormally dry or experiencing moderate drought. But, it is the western states that have been particularly parched.

One of the hardest hit states is California, which is now in its fifth consecutive year of drought. In fact, 100% of the Golden State is currently experiencing some form of drought with 43% in extreme drought. These exceptionally dry conditions have provided the fuel for an early and explosive start to the region’s wildfire season.

Deprived of water, trees in California have not been able to produce the sap that helps protect them from insect infestations. This has left them vulnerable to attack by bark beetles, especially as the temperature warms. Together, the drought and these insatiable insects have increased the rate of tree mortality in the state over the past few years. According to a recent survey by the U.S. Forest Service, 66 million trees have died in the Sierra region of California since 2010. That is an increase of 26 million since the last count in October. Sadly, as the drought continues, more trees are expected to die, further elevating the risk wildfires.

The Drought Monitor is a weekly publication produced by a partnership of government agencies, including the National Drought Mitigation Center, the United States Department of Agriculture, and the National Oceanic and Atmospheric Administration.

41% of the US is in some form of drought. Credit: US Drought Monitor

41% of the US and 100% of California is in some form of drought. Credit: US Drought Monitor

Heatwave Helps Fuel Wildfires in American West

Wildfire season in the American West typically gets going in the latter part of summer, but this year it is off to an early and explosive start.

As of Wednesday, according to the National Interagency Fire Center, nineteen large wildfires – defined as greater than 100 acres of timber or 300 acres of grassland – are burning in eight states.  These include Alaska, Arizona, California, Colorado, New Mexico, Utah, Washington, and Wyoming.

In Santa Barbara, CA, the Sherpa Fire has burned approximately 8,000 acres of land since it began last week. The Reservoir Fire and Fish Fire, both in LA County, have each scorched thousands of acres and forced more than 750 homes to be evacuated. In New Mexico, 24 homes have been destroyed by the Dog Head Fire, which has blackened almost 28 square miles of land near Albuquerque. And, in Arizona, the Cedar Fire has charred nearly 42 square miles of the Fort Apache Indian Reservation.

These huge fires are being fueled by years of drought and bark beetle infestations that have turned the region’s forests and brush areas into parched tinderboxes, making them susceptible to any type of spark. On top of that, a searing heat wave has now exacerbated the situation.

A massive area of high pressure, known as a heat dome, has been sitting over the region for days producing extremely hot and dry conditions. On Monday, according to the NWS, Las Vegas, NV saw the mercury climb to 115°F, Phoenix, AZ reached 118°F, and Palm Springs, CA hit a sweltering 122°F.

Although wildfires are part of the ecosystem in the western US, the early start, massive size, and widespread scope of the current fires are rather unusual. They also come on the heels of the 2015 wildfire season, which was the worst in US history with more than ten million acres burned.


Smoke billows over LA as wildfires burn in the nearby hills of Angeles National Forest.          Credit: R. Chiu/AP

Massive Wildfire Burns in Western Canada

A massive wildfire is raging in Alberta, Canada. Situated in the heart of that country’s oil-sands region, it is known as the Fort McMurray Fire.

Charring 772 square miles of parched land since it started on May 1st, it is now one of the worst wildfires the area has ever seen. As of Sunday, according to local officials, more than 1,600 structures have been destroyed and more than 88,000 people have been forced to evacuate.

Only a few days after it began, the fire became so large and intense that it started producing its own weather, including pyrocumulus clouds and lightning.

While the exact cause of the fire remains under investigation, unusually warm temperatures, low humidity, and high winds have been helping to fuel the blaze. But, like many other weather-related events this year, El Niño also played a role. It brought the region a dry autumn and winter followed by a warm spring, which created tinderbox conditions that just needed a spark.

This wildfire, according to the Alberta Emergency Management Agency, is still burning and is expected to take months to fully contain.

The Fort McMurray Wildfire rages in Alberta, Canada. Credit: The Star and CP

The Fort McMurray Wildfire rages in Alberta, Canada.  Credit: The Star/ CP

Pyrocumulus Cloud Forms Over Wildfire in Kings Canyon National Park

Fueled by drought, wildfires have been blazing across the American West all summer.   Sixteen are currently burning in California alone. While hiking in Kings Canyon National Park in the state’s rugged Sierra Nevada Mountains recently, I crossed paths with the “Rough Fire” and saw it produce a billowing pyrocumulus cloud.

Pyrocumulus clouds form when intense heat at the surface – usually from a wildfire or volcanic eruption – causes air to rise rapidly. As it travels upward, water vapor in the air condenses into droplets and forms a cloud. Filled with ash and smoke, the swelling cloud generally appears more grey than white.

Ignited by lightning over three weeks ago, the Rough Fire continues to spread and has even caused parts of Kings Canyon National Park to close. According to the NPS, smoke from the massive fire has also impacted the air quality in and around the park. To date, the fire has charred close to 50,000 acres and is only 17% contained.

Pyrocumulus cloud rising over California's Rough Fire in Sierra National Forest and Kings Canyon National Park. August 2015. Credit: The Weather Gamut.

Pyrocumulus cloud rising over California’s Rough Fire in Sierra National Forest and Kings Canyon National Park, August 2015. Credit: The Weather Gamut.

2015 Wildfire Season on Track to Record Levels in US

Summer is wildfire season in the American West, and it is off to a raging start.

So far this year, according to the National Interagency Fire Center, wildfires have burned 5.5 million acres across the US. That is an area roughly the size of the state of New Jersey. It is also the second highest total (as of this date) in the last 25 years.

As of Monday, 22 large wildfires – defined as greater than 100 acres – are burning in 5 states.  In California’s Napa Valley region, the Wragg Fire has scorched 7,000 acres and forced many residents to evacuate. In Montana, a massive blaze has burned approximately 5 square miles of Glacier National Park since it began last week. The majority of the acres burned, however, have been in Alaska. They have seen nearly 4.7 million acres charred, which is about 85% of the national total to date.

High temperatures and prolonged drought in the West have turned forests and brush areas into tinderboxes that are susceptible to any type of spark. While summer is usually hot and dry in California, the state is enduring its fourth year of drought. Alaska has also been unusually warm and dry. In fact, according to NOAA, they are in the middle of their second warmest year on record, year to date. These warm temperatures helped produce a dearth of winter snowfall, which has lead to drier than normal conditions across a large area of the state.

Overall, wildfires in the US seem to be getting worse. In Alaska, 3 of the worst wildfires have occurred in the last 12 years. In California, 12 of their 20 largest fires have taken place since 2000. In both states, wildfire records date back to the 1930s.

Nationally, summer 2015 is on track to be one of the worst wildfires seasons on record.

Credit: CBS

Wildfire rages in Glacier National Park, Montana. Image Credit: CBS

Worst Wildfire in Washington State History

A massive wildfire is raging in Washington State. Situated about 120 miles northeast of Seattle, it is known as the Carlton Complex Fire.

Starting off as four separate wildfires, they have now merged into one massive blaze. Charring 375 square miles of parched land since last week, it is now the largest wildfire the state has ever seen. As of Sunday, according to local officials, more than one hundred fifty homes have been destroyed, hundreds of people have been displaced, and at least one death has been reported.

Sparked by lightning, this fierce fire is being fueled by drought, unusually high temperatures, and gusty winds.  Currently only 2% contained, weather conditions are likely to change in the coming days and give firefighters a helping hand. Forecasters say cooler, moist air will move into the region and winds should ease. Nonetheless, if this incoming  weather pattern generates thunderstorms more fires could be ignited.

This blaze, according to the National Interagency Fire Center, is just one of 24 large wildfires currently burning in the drought stricken American West.

Carlton Complex Fire rages in Washington State.  Credit: KING5

Carlton Complex Fire rages in Washington State. Credit: KING5


Drought conditions across the American West. Credit: US Drought Monitor.

Smoky Haze Fills the Air in NYC

The smell of smoke filled the air in New York City Monday morning.  Its source was a 1,600-acre brush fire in Wharton State Forest, NJ – about 90 miles away.

Burning since late Sunday, the smoke was trapped near the ground by a local temperature inversion. This is a weather phenomenon where the temperature in the atmosphere increases with height instead of decreasing.  Essentially, the inversion layer acted like a lid and caused the smoke to spread out horizontally rather than vertically.  A low level wind from the southeast then carried the smoke toward the city.

The smoky haze prompted the EPA to issue an air quality alert for the NYC area. With a spike in the pollutant known as “fine particulate matter”, this was the first time this year that the city’s air quality dropped below “moderate” on the agency’s AQI scale.

Smoky haze fills the air in NYC.  Image Credit: WPIX.

Smoky haze fills the air in NYC.  Image Credit: PIX11.