Delays and cancellations caused by early morning fog have led to residual delays of nearly a half-hour on flights into and out of LaGuardia Airport on Wednesday afternoon, the Federal Aviation Administration is reporting.

The FAA said air travelers can expect average delays of about 27 minutes, though some might be much longer.

Travelers are advised to contact their air carriers about possible flight changes.

There are no reported delays at Long Island MacArthur or Kennedy airports.

Early morning fog led to the National Weather Service issuing a dense fog advisory for the second-straight day. That advisory was in effect until 10 a.m.

The Port Authority, which operates the three major metro-area airports, reported weather-related delays at LaGuardia that included at least 20 delayed flights and a handful of cancellations. Fog is also expected Wednesday evening into Thursday morning, the weather service said.

Sunny skies are expected to return Friday -- although there is a chance of showers on Saturday, forecasters said.

The weather service said it could also rain Sunday.

Latest videos