Washington, December 30 (RHC)-- More than 3,000 flights have been cancelled and around 5,000 flights were delayed due to deadly winter storms and floods across the United States during one of busiest travel periods of the year.

On Monday, more than 2800 flights were cancelled, according to data provided by flight-tracking service FlightAware.com. More than 1600 of those cancellations were at two main airports in Chicago, Illinois. Winter weather continued to frustrate American fliers on Tuesday, with significant delays and cancellations reported in the Chicago and New York City regions.

More than 40 people were killed in severe weather in the Southern and Midwestern parts of the United States during the Christmas holidays in the past week. Days of deadly tornadoes and the flooding have led to dozens of deaths in the states of Texas, Alabama, Tennessee, Arkansas, and Illinois.

Parts of eastern Oklahoma, Arkansas, Missouri and Illinois were under flood warnings and flood watches on Tuesday.

Weather agencies say the extreme weather, which also caused flash floods in Oklahoma and blizzards in New Mexico, could continue to wreak havoc for the coming days.

Adding to the misery, the US Geological Survey reported that two mild earthquakes - 4.1 and 3.4 magnitude - shook central Oklahoma on Tuesday, causing power outages in an area already hit by winter storms.