Travel giant Thomson expects a peak in bookings at 9.45pm on what is being termed Sunshine Sunday' based on search and booking patterns over the last three years.
The operator is predicting more than 2 million searches on Sunday and thousands' of customers booking to go on holiday in 2013.
The most-searched-for short-haul destinations are anticipated to be the Canary Islands, Majorca and Greece.
Those seeking guaranteed sunshine are expected to look at Mexico, Jamaica and Thailand, being served from November.
Marketing director Jeremy Ellis said: With Christmas firmly out of the way, many people want a holiday in the sunshine to look forward to. Over the last few years we've seen a trend towards booking holidays earlier and with record bookings over Christmas we're expecting the rush to continue with our busiest online day of year this Sunday. Brits can also take advantage of some of the great January deals available. Good start to the year
Agents have reported a promising start to the new year with customers booking early for their summer holidays.
It has been reported that sales within the industry have risen quickly with an increase of more than 60 percent than 2011 for the Christmas Period.
Destinations that are proving popular are Tenerife and Majorca.
Thomson have reported an increase of more than 30 percent for hits to their website with hits at peak times of between 11 and 12 noon. British Airways saw a 75 percent increase in the number of people booking holidays on Christmas Day compared with last year and a 58 percent rise on Boxing Day. Smaller agents are reporting an increase in customers ready to book rather than receiving 10 phone calls first. A representative from Airflights.co.uk said This could be down to having such a wet year, people are more positive about having some sun for 2013.