The turkey is done, but where are the guests? Winter weather and too much traffic can slow down cars and planes. And then there are those who live around the corner from you but are chronically late for everything. Don't invite them next year. Find prompter friends. But that doesn't solve this year's problem: how to keep food at a safe and appetizing temperature while waiting for dilatory diners. This article will cover holding techniques used by experts.  But first, some basics about food safety and the definition of a cooked turkey.

The general rule is to keep perishable food out of the "danger zone," the temperature at which bacteria grow rapidly. That zone is 40°F-140°F. The usual advice is to avoid leaving perishables in that zone for more than 2 hours, including preparation time. The Ocean Spray cranberry website recommends no more than an hour for turkey. Since your turkey will be on the counter or the table when it's being carved and served, it's wise to keep it out of the "danger zone" as much as possible while it's waiting for hungry guests to arrive. Of course, in order  to know what temperature the turkey is at, you need a food thermometer.

Just to review: How do you know when the bird is fully cooked? Your turkey will be safe to eat when its temperature is 165°F or above in the innermost part of the thigh, the wing, and the thickest part of the breast. Sometimes, if you have a very young bird, pink juices may come out when the turkey is pricked. But don't judge doneness by the color of the juices or the flesh; trust the thermometer. For better quality (less  rubbery meat), it's sometimes recommended to cook the turkey until the white meat is 170°F and the dark meat is 180°F. Don't count on the little timer that comes with the turkey. One little timer doesn't go in deep enough or in enough places to be an accurate indicator of doneness.

The goal is to keep the cooked bird above 140°F without overcooking it and drying it out. Here are some tips for accomplishing that:

• Many Thanksgiving chefs like to leave the turkey on the counter for 20 minutes before carving it. That's supposed to make the turkey taste juicier. It certainly makes it easier to handle and carve. Who wants to fight with a big animal hot enough to burn your hands? Therefore, if your guests are just a little late, the turkey will wait patiently and safely on the counter.

• If you need to keep a cooked turkey hot or warm for a longer period of time, food scientist Dr. Catherine Cutter offers the following advice: Don't carve the bird before the guests arrive. Keeping it whole will keep the cooked poultry meat from drying out. Cover it with foil, and put it in a 200°F oven with a pan of water on the bottom of the oven to keep the bird moist. Even if you choose to ignore Cutter's expert advice and carve the bird before your company comes, the oven-plus-water technique and covering the poultry meat with foil will help to keep the turkey both warm and moist.

• If you have enough oven space, wrap your other perishable hot foods in aluminum foil and also put them in a low (165°F-200°F) oven.

• Suppose your oven is occupied by holiday sides that are still cooking. Food process engineer Dr. Timothy Bowser offers a solution to that problem: "One of my favorite tricks is to cover a hot (or cold) dish with aluminum foil and then add a dish towel on top of that to increase the insulation value. This works really well if you want to keep an item at a constant temperature while it's on the counter, just before serving." Note that the foil-and-towel trick will also help to keep your casserole and anything else either hot or cold, though not indefinitely.

• Buying hot plates (warmers) are a good investment if you serve crowds often.

• Foods that should be kept cold can go back into the fridge if there's room. If not, wrap them with foil and a towel also.