LoCO has a very detailed report from a reader of a Boom in McKinleyville. Litara Angeli writes,

…at approx. 4:30 p.m. @ the Starbucks in McKinleyville on Saturday 12/21[today,] my husband and I (who were both facing in the eastern direction to avoid glare from the windows) felt a sudden, subtle “burst” in our ear that was somewhat painful. We felt it come from the West.

I thought it was an earthquake, but my hubby said that was the sound a sonic boom makes, so he did some quick research. Apparently the booms have been heard in Eureka quite often recently - since November?

A jet, maybe? He seemed to witness a very slight, sudden flash of white or yellow light in the air, because my husband has frameless aviator glasses that catch the glare due to the polarization of his thick prescription lenses. He said it was almost like a light bulb burst. The boom we felt in our ears was almost like pressure, you know, when you’re up in an airplane cabin - but the noise was so subtle, it was almost like a bird clipped us as it flew past our ears. (You know, the way hummingbirds do.)

So the slight noise, uncomfortable “pressure” felt in our ears, and a very slight yellowish white tint was witnessed by us both. It’s the time of the year for meteorites, and 2013 has been one of the most active years for astral phenomenon. Could be that as well.

Also there was a report from Cooper’s Gulch area of Eureka around 2:40 P.M.