Cooking a turkey on a Weber gas grill may require a few more steps than traditional oven roasting, but results in a much crispier and well-browned skin over juicy turkey meat. Weber gas grills vary in size and accessories, but even the smallest should be able to accommodate a whole turkey. Weber recommends indirect grilling on gas grills, with the turkey placed on a roasting rack set inside of a disposable aluminum foil pan. Season and prepare your turkey however you prefer before adding it to the hot grill, then turn it routinely to ensure an evenly browned turkey.
Remove the giblets from a thawed or fresh turkey and pat dry with paper towels. Brush the bird inside and out with canola oil or butter, then season the outside to taste.
Open the lid of your Weber grill before turning on the gas to avoid fumes collecting inside. Underneath the grill, slowly turn the valve on the propane tank all the way. Wait for 1 minute to make sure the gas has traveled completely through the gas line.
Turn all the burners on high for about 10 minutes with the lid closed to preheat the grill. When the grill is fully heated, clean the grates with a grill brush if necessary, then turn down the burners to a medium temperature of about 350 degrees Fahrenheit. Turn off one of the burners entirely, which is where the turkey will go for indirect grilling.
Sit a roasting rack inside of a large aluminum foil pan. Place the turkey on the rack, breast side down. Tie the legs together securely with twine, cutting off any excess string.
Place the turkey pan directly over the part of the grill that is not lit and close the lid. Allow the turkey to cook breast side down for the first hour, then carefully turn the turkey breast-side up using heavy-duty oven mitts and paper towels. Tuck the wing tips under the shoulders.
Continue cooking the turkey with the lid closed, turning it about every 45 minutes to an hour for even browning. A 10- to 18-pound turkey should take roughly 2 to 3 hours to fully cook at 350 F on a grill. The turkey is ready when a food thermometer inserted into the thickest part of both thighs is between 170 F and 175 F, and the breast has reached at least 160 F.
Remove the turkey from the grill and cover with aluminum foil, allowing it to rest for 20 to 30 minutes. The temperature will rise at least another 5 degrees, ensuring that the breast will reach 165 F, the minimum temperature for safe consumption of poultry, according to FoodSafety.gov.