We need to close the Pacific Northwest Radar Gaps

Doppler radar is one of my favorite tools for viewing weather data. Its amazing to me that using radio waves, we can see light rain and snow, tornadoes, and fine details in hurricanes. Not only can we see where these are, but we can also estimate wind speeds, freezing levels, and hail sizes – all technology that meteorologists of the early 20th Century couldn’t even dream of available at the palm of my hand.

In the United States, we have what is perhaps the most robust weather radar network in the world. Smaller nations like Barbados have near-100% radar coverage for their country, but that is because the island nation is small enough that one Doppler radar is all that is needed to provide full coverage. In America, coverage is significant east of the Rocky Mountains, but for many reasons, there are several gaps in the West that need to be addressed. One of these can be found in Central and Eastern Oregon.

Everywhere in white on the map above is lacking Doppler radar coverage below 10,000 feet above ground level, with several large and clear gaps in the western half of the country. Dennis Mersereau further explains in this Washington Post article that to have a clear vision of what’s going on, we need to have universal coverage below 6,000 feet above ground level. That takes out all of the blue on that map above as well.

This doesn’t leave us with a whole lot to go off of here in the Pacific Northwest. While Seattle, Portland, Spokane, and Boise all have excellent coverage, there are several moderate-sized cities left out. This includes the entire I-5 corridor from Salem south to Medford, nearly all of the US 97 corridor, including Bend, Yakima, and Wenatchee, and nearly all of Eastern Oregon. Most importantly, though, is the lack of dependable offshore radar coverage from California’s Redwoods north to the Columbia River.

The simple fact we have to face here before going on is that radar coverage is harder to make happen in the west than in the east. This is because of the terrain we have. The radio waves emitted by Doppler radar sites work similarly to those on the FM Radio band. Go around a mountain and it’s gone.  Areas like Central Idaho just aren’t feasible for us to have low-level radar coverage.

For everywhere else outside Central Idaho, we need low-level radar coverage for a variety of reasons. Here are just a few:

1. We need it off the coast to help sense and predict incoming storm systems. We don’t have much weather data coming from the Pacific Ocean, despite the fact that many of our strongest storm systems come from there.
2. We need better coverage in Central and Southeastern Oregon to be able to determine snowfall rates in these remote regions, which ends up in streams and rivers in the Spring.
3. We need better coverage in the southern Willamette Valley and on the east slopes of the Cascades to aid in weather observation and short-term weather alerts for the moderate-size cities like Eugene and Yakima.
4. We need better coverage on the east slopes of the Cascades to track and predict dry thunderstorms, which often spark fires.
5. We need better coverage in eastern Oregon because thunderstorms form in the remote areas and often move into more populated regions like the Columbia Basin. One of these produced a funnel cloud in Kennewick in 2016.
6. We need better coverage throughout the region to help predict landslides through the Pacific Northwest, especially in fresh burn scars.

There are countless more reasons to improve the radar network in our region, but until the community at large gets behind the effort, nothing will change. America’s newest Doppler radar is located on the Washington Coast near Aberdeen. Built in 2011, it took 15 years of lobbying by community members, leaders, and scientists to secure funding for the site. Before it was built, there was nearly no offshore coverage north of California at all.

The biggest influence in securing this site was two windstorms that struck the region back to back in 2007. These caused extensive flooding, forcing the closure of Interstate 5 for several days. In 2008, Senator Maria Cantwell from Washington began work to secure funding for the site amid what Cliff Mass called “unenthusiastic bureaucracy.”

Enhancing our radar network will be expensive, but mitigation efforts often are. Having a better radar network in the Pacific Northwest will help provide better forecasts for the entire country because we are often on the front lines for storm systems that go on to impact much of the United States. These forecasts will help prepare us to protect ourselves and our property. Just because damaging storms don’t seem to happen as often here as in other parts of the world doesn’t mean they don’t happen at all.

It is my hope that we will be able to secure funding for new radar sites throughout the Pacific Northwest allowing us to predict damaging weather events rather than being caught by surprise by them, but this will only happen if we actively reach out to our elected leaders and instill in them an understanding of why we need this equipment.

For further reading:

• U.S. radars have come a long way, but gaps in coverage remain a big risk (Washington Post)
• The Oregon Coastal Radar Gap: A Serious Problem for Northwest Meteorologists (Cliff Mass Weather and Climate Blog)
• The Other Radar Gap: The Eastern Slopes of the Cascades (Cliff Mass Weather and Climate Blog)
• Langley Hill Radar (University of Washington)
• Washington Coast Doppler Radar (NWS Seattle)