When a powerful string of thunderstorms ripped across the region last summer, few people were prepared for their intensity.
The storms surprised forecasters at the National Weather Service who didn’t expect winds so powerful that traffic would be stopped and electricity cut off.
Now, a new $2.2 million radar system going up west of Airway Heights will give forecasters a far better look at approaching storms.
For the public, this means fast and accurate warnings of hazardous weather, such as snow, freezing rain, hail or heavy winds.
Even when the weather isn’t a threat, television viewers will be able to watch the progress of storms across the region starting in March.
On Wednesday, workers installed a 30-foot dome atop the new radar tower on Rambo Road, where Spokane’s National Weather Service office relocated earlier this year.
“This is going to be a dramatic improvement,” said Spokane meteorologist John Livingston.
The radar is part of a $4 billion upgrade of the National Weather Service over 10 years. It includes some 120 new weather radars, satellites and a sophisticated computer system.
Another 41 weather radars are being installed by the Department of Defense and the Federal Aviation Administration in a joint radar network.
Forecasters at Fairchild Air Force Base will get information from the new radar, said Major Rob Rizza, weather flight commander. That information will help pilots avoid approaching thunderstorms.
Widely known as Doppler radar, this new eye on the sky is really a marriage of high-speed computers with a type of radar technology that’s been around for years.
The military has long used a variation of Doppler radar to detect the speed and direction of oncoming aircraft.
It is based on a principle of physics known as the Doppler effect, in which the sound given off by moving objects changes depending on the direction.
For example, the whistle of an approaching train deepens after the train reaches a crossing and begins moving away. A passing ambulance has the same sound effect.
The Doppler system reads the different frequencies of radar beams reflected by water drops or dust particles moving within clouds up to 140 miles away.
A high speed computer assembles the information on colored maps, which show the direction the clouds are moving.
Doppler radar is so sensitive that it can detect dangerous levels of turbulence within clouds.
This technology is particularly useful in the Midwest and southeast United States, where tornados and hurricanes are common.
Spokane is one of the last areas in the country to get the new radar system, in part because there is less severe weather here than elsewhere.
In the past, forecasters in Spokane used images from aviation radar to track storm movements. Their accuracy was limited.
The new radar will give weather watchers a better look at how much rain or snow is falling at any given time over the entire region, and the radar maps can be used to predict the timing and duration of approaching storms.
The Doppler system already is in operation near Seattle, Portland and Missoula, but leaves a blind spot of storm movements across the Inland Northwest.
Radar maps now seen on TV here don’t show storms in Eastern Washington, North Idaho and eastern Oregon.
When radars go into operation in Spokane and Pendleton, those TV maps will start showing storm movements here, Livingston said.
This radar is most reliable for predictions of 6 to 12 hours in advance, but less useful for next-day forecasts.
“It will allow us to get a much better handle on what’s happening now,” Livingston said.
, DataTimes ILLUSTRATION: Graphic: New eyes on the sky
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