The speed radar squeals, clocking a gray Kia Optima going 90 mph in a 70 mph zone just south of Exit 36 on Interstate 5 northbound during Tuesday's rush hour.
The driver doesn't notice Trooper Alexis Tonissen in the neighboring lane. She drives an unmarked white Chevrolet Impala with tinted windows, its lights hidden in the grille and inside the windshield.
Even if you could tell it was a cop car, aggressive or speeding motorists often aren't paying enough attention to notice, she says.
After pulling over the Optima, the 62-year-old driver says he's just trying to get home to Tacoma. It's a common excuse that Washington State Patrol troopers hear when they catch speeders.
They didn't realize they were going so fast. They were just going with the flow of traffic.
Many motorists on this stretch of I-5 near Kelso, Tonissen explains, are just passing through. She cites the man for going 10 mph over the speed limit, instead of 20, which would be considered aggressive driving. People don't intend for their car to be a weapon, Tonissen says, but when they drive aggressively, the car becomes one.
Tonissen is part of the State Patrol's Aggressive Driving Apprehension Team, which aims to reduce road rage, aggressive driving and speeding by strategically placing unmarked police vehicles on state freeways.
She's been with the patrol for six years and been part of ADAT for three. The team's methods differ from typical patrol units, which will drive five miles or more over the speed limit. An ADAT member stays in the middle or right lane, hovering just under the speed limit to watch for drivers that blaze by.
"You have to really watch traffic," says Tonissen, who constantly scans the road and her mirrors.
Her radar clocked a passenger vehicle driver going 131 mph last summer and a motorcycle at 140 mph in February. She couldn't catch the motorcyclist.
Most of the time, speeders are where you would expect them to be -- in the left lane.
"Look," she says, pointing out the crowded left lane and wide-open right lane. A left-lane driver might tail other cars until they switch lanes, a behavior known as "pushing" by State Patrol troopers.
Speeders are obvious, she says, as she parks her Impala on the shoulder of an interstate exit ramp. From her perch, she can differentiate speeding bullets from vehicles that are just going with the traffic flow.
In the first two months of 2013, State Patrol troopers cited 2,305 Clark County drivers for speeding and 406 for aggressive driving. The number of motorists cited for these violations has increased over the last five years, despite relatively flat average daily traffic volumes on most local freeways. Several spots along Highway 500 in central Vancouver, however, measured clear increases in traffic, according to annual traffic reports published by the Washington State Department of Transportation.
When gas prices spiked, Tonissen saw the number of speeders go down. Now that prices have leveled out, speeding incidences are back up. Ironically, one of the excuses she hears from speeders is that they're almost out of gas and were on their way to a gas station. That doesn't make any sense, she says. The faster you go, the more gas your vehicle guzzles.
Cops typically see more speeders on the weekend, during rush hour and when the weather is nice, making summer the season of speed.
There's nowhere in Vancouver that has a speed limit higher than 60 mph. The speed limit climbs to 70 along the I-5 corridor in Ridgefield, just past the exit to the Clark County Event Center, and stays there into Lewis County.
On Feb. 27, a Gresham, Ore., man led police on a 12-mile, high-speed chase between Fairview, Ore., and Vancouver. Daniel Edstrom, 23, drove an Acura Integra at speeds of more than 100 mph north on Interstate 205, where he was met with spike strips that caused the car's tires to disintegrate.
The car was disabled after it took the Mill Plain exit and spun out in the 400 block of Northeast 112th Avenue. Vancouver police eventually found Edstrom in some bushes behind Oscar's Bar & Grill and took him into custody. He was sentenced to 60 days in jail for taking a vehicle without permission.
Edstrom fits the typical profile of an overwhelming amount of speeders -- he's a young man.
Clark County Sheriff's Office data from 2012 show a spike in speeding among drivers age 17 to 21. The biggest culprit? Nineteen-year-old men.
Tonissen tries to pull over a Chevrolet Cobalt driven by a 19-year-old man. She flashes her red and blue lights, but he doesn't notice them. When she blares her siren, he slams on the brakes and pulls over to the left shoulder of I-5 southbound. The teen, who had been speeding up and slowing down erratically and darting into the left shoulder, turns out to be very tired.
"He's tired and speeding? It's not a good combination," Tonissen says.
On average, it takes 1.5 seconds to respond to a traffic hazard after seeing it, Finn says. In that 1.5 seconds, a vehicle going 100 mph will travel an additional 220 feet before the driver reacts. How long it takes a driver to notice and react to a traffic hazard depends on their driving skills, their level of distraction and whether they're impaired.
If the driver slams on the brakes right after those 1.5 seconds, the vehicle still has to decelerate and disperse all that energy before coming to rest. The distance it takes to stop depends on the vehicle, its speed and road conditions. Wet or icy conditions affect the kinetic friction between the tires and the road surface.
The science of speed says that the faster you go, the longer it takes to stop. Your car weighs the same at 20 mph and at 120 mph, but has more force the faster it travels.
The bottom line is that a car continues traveling while it's braking, adding to the total distance it takes to stop. The faster you go, the more distance needed to avoid a serious collision. On average, speeding causes 450,000 injuries each year and about 6,500 deaths nationwide.
Driving dangerously doesn't just mean topping 100 mph.
Egregious speeding in a school, construction or residential zone can be just as dangerous as freeway speeding, depending on the circumstance. Let's say a motorist going through a school zone is traveling at the most commonly ticketed speed by Clark County deputies, 50 mph. Speed limit signs flash, alerting drivers to go 20 mph in the school zone. If the driver struck a child, there's a high likelihood of killing the child, says Vancouver traffic Sgt. Pat Johns.
Johns says he'll occasionally catch super speeders on city roads, once pulling over someone who was traveling 99 mph on Southeast 164th Avenue, between Poplar Street and Fourth Plain Boulevard. In 2012, sheriff's deputies caught 12 motorists traveling over 90 mph on county roads.
Speeding convictions remain on a driving record for five years. For insurance purposes, they stop showing up after three years. Employers looking to hire someone whose job duties include driving, however, can see that entire five-year record, says Brad Benfield, spokesman for the Washington State Department of Licensing. The fees are based on a sliding scale, so the faster a motorist drives over the speed limit, the pricier the ticket.
Drivers can also expect a speeding violation to bump up their insurance rates.
"If you have a bit of a lead foot, it's one of many things to consider when you're out there on the road," says Brad Hilliard, spokesman for State Farm Insurance in the Pacific Northwest.
Multiple factors determine how much a motorist will pay for car insurance; their driving record is one of the most critical. According to Insurance.com, speeding 30 mph over the limit raises rates by 15 percent.
The costs of speeding and aggressive driving are totally avoidable and controllable, troopers say -- drivers are the ones governing the gas pedal.