Christmas UPS, Fed-Ex Delivery Delays 2013: Companies Under Fire on Twitter With all of the bad weather, there were empty spaces under the trees, thanks to a christmas day nightmare. A foulup by fedex and u.P.S. Thousands of presents weren't under the trees where they should be. The shipping companies said bad weather and overloaded systems have companies seeing red. Rob nelson has more on this. Good morning to you, rob. Reporter: Good morning to you, josh. At shipping centers all across the country today, including this one behind me in downtown manhattan, it is going to be, as you said, a very busy day. Companies trying to get back on track, after some delays that some folks said ruined their christmas. Frustration across the country is clear. U.P.S. And fedex packages were delayed, ruining christmas for thousands of customers. With one customer tweeting, due to u.P.S. Being awful, my mom did not get all the gifts she wanted to give for christmas. Looks like christmas is next week. Another tweeted, thanks, u.P.S., for ruining christmas. Does a promised delivery date not mean anything to you? Officials will not say the exact number of packages that didn't make it. But they are giving a santa-worthy list of reasons. Incorrect projections about the volume of this year's business. More options online that increased shipping demand. And icy weather, that slowed air travel in parts of the country. Despite those factors, curt cohen, the ceo of u.P.S., Spoke this month to cnbc, about the decision not to increase the number of seasonal workers from last year's 55,000. We became more efficient to use technology on the ground for routing and scheduling, to increase demand. Reporter: Both companies say the normal delivery schedules will resume in full force this morning. One u.P.S. Official blamed, quote, a perfect storm of factors for its problems this year. But that did little to soothe irritated customers. I've been waiting since christmas eve. Nothing is going to be under the tree. Reporter: Fedex also caught a lot of heat on twitter yesterday. But officials there say of the nearly 300 million packages they delivered between thanksgiving and christmas, only a very few did not arrive on time.