A Macy's store is seen at Herald Square on December 11, 2023 in New York City.Michael M. Santiago | Getty ImagesInflation may have cooled, but retailers are still staring down a holiday season with plenty of uncertainty.Several hard-to-predict factors will influence consumers' spending, as they deck the halls and look for the perfect gifts. Volatile weather, election distraction and a deal-hunting mindset may shape the season. And fewer days between Thanksgiving and Christmas than last year will put shoppers on the clock.Yet there's reason for optimism for retailers: Shoppers are feeling more upbeat and plan to spend more compared with last holiday season, according to an annual survey by consulting firm Deloitte and a separate forecast by the National Retail Federation.Holiday spending in November and December is expected to increase by 2.5% to 3.5% compared with 2023 and range between $979.5 billion and $989 billion, according to the National Retail Federation. That's a more modest increase than the 3.9% year-over-year jump from the 2022 to 2023 holiday season, when spending totaled $955.6 billion. The NRF's figure excludes automobile dealers, gasoline stations and restaurants.Shoppers expect to spend an average of $1,778 on the holidays this year, 8% more than last holiday season, according to consulting firm Deloitte's survey. The survey, which included about 4,000 consumers and was conducted in late August and early September, attributed that spending increase to a more favorable economic outlook, a perception among respondents that prices would be higher and more willingness to spend among higher-earning households with an annual income of between $100,000 and $199,000.Low unemployment, a return to more typical inflation levels and a rec ...