This brilliant colour is caused by IIV-31 (Isopod Iridescent Virus). I've been checking hundreds of pill bugs over several years for this unusual phenomenon and my persistence finally paid off!
Sadly, this total colour change is usually the later stage of the virus; once a pill bug is this bright it generally doesn't have much longer to live.
yellow or golden form
Growing in Seattle underground
The sharp rise in temperature from the last few days seems to have prompted huge numbers of ants to have their nuptial flights. I was at Warm Springs BART station where I found three species of alates being drawn to the bright lights of the station