Owls are typically symbolic of wisdom or a significant life change, though some cultures also see them as a symbol of someone who is reaching out after death. As owls are nocturnal, it can be disconcerting to see an owl during the daytime, and though many may take this as a bad omen, it is not necessarily so. In most cases, it's likely that the owl's sleep was disturbed and it is simply looking for another place to rest.
In many cultures, especially Native American cultures, the owl is seen as someone who was wise during his or her time on earth and who has come back to protect loved ones. Some Native Americans believe that seeing an owl, especially one that is vocalizing, may signify that the deceased is trying to send a message to the ones they left behind.
The most common reason that an owl would be seen during the daytime is when its sleeping, eating and hunting patterns have been disrupted. Seeing an owl during the day is often less about spiritual or ritualistic meanings and more about the surrounding environment. When there is a lot of human influence in a forested area, all of the wildlife in the area will be disrupted, including owls.