Here’s the good news for retailers: consumers are in the mood to spend heading into the holiday season, which is expected by the National Retail Federation to be the best in years. And here’s the bad news: stores will have anything but a Merry Christmas if they haven’t raised their e-commerce games ahead of Yuletide.

Data firm eMarketer is forecasting e-commerce sales will rise 17% this holiday season, five times faster than in stores. And online sales will hit a major milestone, generating 10% of all spending for the first time. The momentum is undeniable: in 2015, more shoppers went online than to stores over Black Friday.

The big winner here is Amazon amzn —BloomReach says 50% of all e-commerce searches start on the site. To have any hope of competing, brick-and-mortar behemoths are scrambling to catch up. wmt now offers 20 million products, up from 11 million in July, while Target tgt has doubled the number of stores that deliver online orders.

Expect more to beef up their online offerings as holiday shopping kicks into gear.

A version of this article appears in the November 1, 2016 issue of Fortune with the headline “Stores’ Bleak Black Friday.”