New electronic message signs on Interstate 5 will help improve safety on the Siskiyou Summit by displaying speed limits that change based on weather conditions.

The Siskiyou Summit, also called the Siskiyou Pass, is the highest mountain pass on the I-5 corridor, with an elevation of 4,311 feet. Located south of Ashland, the pass can vary from dry and clear to icy or snowy.

The signs will be located on northbound I-5 between the Oregon-California border and Ashland. They’ll go live by Jan. 1, according to Oregon Department of Transportation.

ODOT said three of the six new signs can show drivers a legally enforceable lower speed limit. Computers will automatically adjust speed limits displayed on the electronic, black-on-white speed signs based on weather and pavement conditions on the summit. The computers gather information from sensors that can measure factors such as road surface traction, humidity, air temperature and visibility.

When conditions improve, speed limits will be automatically raised again, ODOT said.

“Drivers going too fast for the changing conditions often get surprised on the Siskiyou Summit,” ODOT District Manager Jeremiah Griffin said in a press release. “High speeds frequently lead to crashes and delays, no matter what time of year. These new variable speed signs will be an important safety tool.”

Data from the Federal Highway Administration shows variable speed limits reduce the number and severity of crashes, especially during bad weather.

The variable speed limit signs are regulatory, meaning Oregon State Police can ticket drivers for going over the displayed speed limit. To avoid confusion, the new electronic signs will replace the traditional static speed limit signs.

In addition to the three variable speed signs, there are two dynamic curve warning signs. They show drivers their speed as they approach two sharp curves near the exit to the Mt. Ashland Ski Area and a railroad trestle. The electronic curve warning signs are similar to ones on I-5 at the Myrtle Creek curves between Grants Pass and Roseburg.

The sixth new sign, a variable electronic message sign at the summit, will be used to update drivers on conditions or hazards ahead. The information also will help update ODOT staff and emergency responders about such incidents.

The new signs are part of a recent $35 million I-5 improvement project between the California border and Ashland.

For updates on road conditions throughout Oregon, see tripcheck.com.