A Delta flight on a slushy runway at John F. Kennedy International Airport in New York. (Kathy Willens/Associated Press)

If you’re flying today, take along a good book and be prepared for delays. A week that starts with heavy snow in New York takes a while to right itself, and there’s more snow forecast for the Big Apple tonight and tomorrow.

When the big three airports serving New York — JFK, LaGuardia and Newark — are hit with cancellations and delays, it quickly ripples through the nation’s aviation network.  Newark had 152 flights cancelled on Monday morning and already was reporting dozens of flights cancelled or delayed Tuesday, according to FlightAware. The other two airports were reporting about three dozen delays.

In the Washington region, where most of the precipitation from the same big East Coast storm fell Monday as rain, morning delays were being reported at all three of the big airports, with Reagan National taking the lead with a dozen.