Caran Johnson, of Vancouver, Washington state, well known in local social-media circles for her tweets on Clark County traffic, began tweeting about a two-vehicle collision shortly after it happened yesterday afternoon.
As the afternoon wore on, she tweeted that she was growing concerned her husband might be involved because he was late arriving home, KATU-TV reported.
After the crash, the mother of two from Salmon Creek wrote how she "hates that section"of the highway.
"Too many on ramps, speeders and too few lanes," she wrote.
After she had sent about 10 tweets about the crash, Johnson realised her husband would have used the roadway to get home from work.
"I'm trying not to panic...he's not answering his phone," she wrote. "And he's late."
As Johnson got more and more frantic, other Twitter users tried to console her.
About two hours after her first tweet, she got confirmation. Craig R Johnson, 47, was pronounced dead on scene.
His car veered across a grassy median and collided head-on with another car.