Howard Baughman of Catonsville says he has lived nearly 83 years and sees occasional references to "traces of rain and traces of snow." "I have never seen 'traces' quantified, however. Would you please clear this up for me?" Sure. Forecasters generally record a "trace" of rain or snow when it is evident, but too slight to measure. According to the Northeast Regional Climate Center's weather glossary, a "trace" of snow is less than a half-inch in depth. A trace of rain amounts to less than .005 inch.