Oregon eclipse traffic
Cars are lined up on Highway 26 heading east from Prineville, Ore., several days before the total solar eclipse. (Ochoco National Forest Photo)

It’s prime time at last for the Aug. 21 total solar eclipse, America’s first coast-to-coast dose of totality in 99 years.

Maybe you’re a veteran eclipse-chaser who’s been preparing for this since 1979, the last time a total eclipse was visible from the mainland U.S. Or maybe you’re a newbie who just heard that the moon is going to cover the sun on Monday.

Either way, it’s not too late to enjoy the eclipse, whether you’re planning to get within the 70-mile-wide path of totality or stay at home. But you do have to be prepared, especially if you haven’t done any planning until now.

The bad news is that traffic and accommodations are already getting jammed up, and viewing equipment is in vanishingly short supply. The good news is that it takes as little as two pieces of paper and a pin to get a good look at the partial solar eclipse.

Listen to our podcast below, and continue reading below for what you need to know.

What you’ll see, and where

Solar eclipses occur when the moon lines up in its orbit precisely between the sun and Earth, casting a shadow on our planet. On Monday, all of North America will see at least part of the sun blocked by the moon. In Seattle, for instance, about 92 percent of the sun’s disk will be covered at the eclipse’s peak, at 10:20 a.m. PT Monday. That’ll make the midmorning sky as dim as sunset.

The sun will be totally blotted out along a 70-mile-wide path that stretches from the Oregon coast to South Carolina’s shore. Darkness will sweep from west to east, morning will turn into night, and in a clear sky, the stars will come out. Daylight will sweep back in about two minutes later.

Eclipse map
This map shows the track of totality passing over the United States on Aug. 21. Click on the image for a larger PDF version. (NASA Map)

NASA has set up a interactive map that lets you zoom in and click to find out what the viewing circumstances will be for anyplace on Earth. (Subtract 7 from the UT time that’s listed to get PT.) Generally speaking, the partial phase of the eclipse begins a little more than an hour before the peak, so it’s worth your while to start watching early.

The intermountain region of Oregon and Idaho is one of the hot spots for eclipse-chasers because the historical record suggests it has the best chance for clear skies in the path of totality. Now that the eclipse is nearly upon us, that suggestion is borne out by the weather forecast.

The outlook is encouraging for Salem and Corvallis in Oregon’s Willamette Valley, but not as good for the Oregon coast. In Seattle, meanwhile the weather forecast promises sunny skies on Monday morning.

Be sure to check the National Weather Service or your favorite weather website for the latest forecast. The Washington Post is putting out a daily cloud forecast for Eclipse Day across the country.

How to see it safely

Staring at the bright sun is never a good idea, even if more than 90 percent of it is covered. It’s more tempting to try to do that when a solar eclipse is under way, but to save your eyes from potentially permanent damage, you need to take protective measures.

One way to do that is to look at the sun through specially made eclipse glasses. Sunglasses or other jury-rigged solutions won’t cut it. If you haven’t already procured glasses or filters, it may be too late. Virtually all of the vendors are sold out. Some glasses may be made available at eclipse-related events, such as the Seattle Public Library’s presentations and viewing parties, but don’t count on it.

Pinhole projection
Projected images of the eclipsed sun are likely to be all over the place on Monday. GeekWire’s Alan Boyle points to images of the sun projected through an office window blind that will look like tiny crescents on Eclipse Day. (GeekWire Photo / Kurt Schlosser)

The best alternative is to make a pinhole projector. The simplest configuration involves poking a pin through a sheet of paper, and then projecting a circle (or crescent) of sunlight onto another sheet. But you can get a lot fancier. Pinhole projectors have at least one advantage over the glasses, in that you can stand around with your friends to ooh and ahh as the eclipse progresses.

In addition to the library’s events, the Museum of Flight is planning an eclipse-viewing party that starts at 9:30 a.m. Monday. NASA scientists will drop in for a visit after their airborne observing session.

If you’re heading into the totality zone, you’ll still need eye protection to look at the partially eclipsed sun. But once the sun’s disk is totally covered, you can take the glasses off and feast your eyes on the delicately glowing corona that surrounds the black hole in the sky. Just make sure to put the glasses back on once totality ends.

Driving to it

Hotel reservations in the zone of totality were snapped up months ago, and campsites are getting scarce as well. Fully equipped RV sites have been going for as much as $1,500 a night, or even more for “glamping” accommodations.

There are still smatterings of commercial campsites around Madras, Ore., but they are generally packaged as multi-night stays. Check this website, but be prepared for a lot of “sold-out” notices.

If you’re thinking about heading out on Monday morning and driving into the path of totality, think again: Traffic tie-ups are already being reported in central Oregon, where two-lane roads are the norm, and not even Interstate 5 will be spared on Eclipse Day.

Another option might be to head into the totality zone over the weekend and luck out on finding a camping spot, or just camp out in your car. That strategy carries risks, of course. One big worry is that travelers could set off an “eclipse apocalypse” by sparking Western wildfires. Follow the guidelines for safe camping: Open fires are generally a no-no, and don’t park on or drive over dry grass.

Oregon State Police will be out in force to keep traffic moving and shoo away people parking along the side of the road. The National Guard is also on standby.

If you’re traveling, make sure that you keep the gas tank filled, stock up on water and food, be prepared for on-the-road emergencies, and know where you’re going. Oregon’s TripCheck website can help you plan your trip. (There’s even a mobile version.)

Seeing it on TV and online

You can experience the total eclipse even if you can’t get to the totality zone, and even if the skies are cloudy all day. Most TV channels will have at least some live coverage, generally starting at 10 a.m. PT Monday. Some outlets are making a special effort, on air and online:

So when’s the next one?

Although it’s been 38 years since the last total solar eclipse on the mainland U.S., we won’t have to wait that long for the next one: Another coast-to-coast eclipse is coming on April 8, 2024, with the path of totality stretching from Mazatlan, Mexico, through Dallas and Cleveland, to the rugged coast of Newfoundland.

Based on the hubbub over this month’s event, it’s not too early to start making plans.

Like what you're reading? Subscribe to GeekWire's free newsletters to catch every headline

Job Listings on GeekWork

Find more jobs on GeekWork. Employers, post a job here.