Pity the lowly snow globe with white flakes raining down on a snowman or Santa Claus tucked inside its dome.

Try packing this favorite travel souvenir in your carry-on luggage and taking it through an airport security checkpoint this holiday season, and chances are you’ll have to leave it behind.

“Snow globes are not permitted to be carried through security checkpoints,” said Transportation Security Administration spokesman Dwayne Baird.

The reason is that the globes contain liquids, and TSA rules say that only liquids, gels or aerosols in containers of 3 ounces or less are allowed through security in carry-on bags.

The containers must fit into a quart-sized zip-top plastic bag, one bag per passenger, to limit the total volume of liquid and lessen the threat of someone using the contents as explosives.

Anyone who’s tried to take a jar of their grandmother’s homemade jam or even a bottle of water through airport security knows the sinking feeling of having it confiscated and tossed in the trash because it doesn’t meet the test.

What about a small snow globe?

“I would think they would just say ‘no,’ because they can’t really determine how many ounces are in there,” Baird said.

Two solutions: Pack the snow globe in your checked luggage, or wait until you’ve passed through airport security and buy one at an airport shop. Once past security, you’re free to buy liquids of any size and take them on board.