STATE COLLEGE – Icy conditions this morning caused numerous crashes, prompted interstate speed limit reductions and closures, and triggered the brief shutdown of a Berks County airport. Freezing rain fell on central and eastern Pennsylvania, but advisories were later canceled in areas where the temperature warmed enough to produce only rain. Reading Regional Airport had to close for 10 to 15 minutes when airport manager Terry Sroka said the icy conditions meant “braking action was nil” on the runways. He said only one plane was affected. Crashes prompted state transportation officials to close Interstate 80 in two places in central and western Pennsylvania, and interstate speed limits were reduced to 45 mph in several counties.