The U.S. Navy Blue Angels returned to take flight over Lake Washington during the Seafair Air Show this past weekend. Above, condensation trails stream off the wing tips and leading edges of Blue Angel No. 5 during Saturday’s performance, viewed from Slater Park. The condensation trails form when maneuvers — in this case, a tight turn — cause a drop in air pressure, which drops the air temperature, causing moisture in the air to condense. It is most common on humid days.