PORTLAND, Ore. (KOIN) — The Portland area is expected to see its heaviest rain in over two months on Thursday, which could hinder drivers who have become accustomed to this summer’s mostly dry conditions.
KOIN 6 Meteorologist Josh Cozart forecasts that the city will see more than a quarter-inch of precipitation by 11:30 p.m. on Thursday evening, with rain starting in the early morning hours.
This would be Portland’s greatest rainfall since mid-June when residents saw 0.98 inches of rain.
The Oregon Department of Transportation says precipitation can cause unsafe road conditions at any point of the year, but the first storm after a dry stretch of weather can be particularly hazardous for drivers.
“Fresh rain mixed with oils can be more slippery than regular rain,” ODOT explained in its Summer Storybook. “Engine, transmission and power steering and other oils and grease build up on the road. When mixed with fresh rainwater, the road can become slick.”
According to the Federal Highway Administration, 75% of weather-related car accidents happen due to wet pavement, while 47% of them happen during rainfall.
To prevent further weather-related collisions, ODOT urges drivers to check their tires, brakes, defrosters and windshield wipers before heading out on the road.
The agency also advised motorists to leave up to three times more space between them and other vehicles, and to reduce their speed to prepare for sudden stops.
Hydroplaning is another concern during wet weather conditions. Transportation officials said it can happen at a speed as low as 35 mph. If this does occur, drivers should ease off of the accelerator.
Experts warn against slamming on the brakes, but ODOT says motorists can lightly press them to gain control of the car.
Additionally, drivers are advised to turn on their headlights and turn off cruise control during wet weather conditions.
“When it’s raining, be cautious and give yourself more time to get where you are going,” ODOT said.