Possible Temp drop.

[KevinK]

.....A few minutes or a few hours won't hurt anything. It takes a while for much to change (depending on how cold it is outside & how insulated your home is).

...because they had no generator back-up & no preparations.

....Incidentally, the heat packs ('hand-warmers') are safe to use (nothing leaks, normally) & are similar to those used in shipping snakes.

It's almost like someone said that already lol