A hutch that copes in mild weather can fail in a storm
Outdoor rabbits and guinea pigs manage ordinary cool nights well in a dry, draught-free hutch, but a storm changes every part of that equation at once: wind drives rain sideways under covers, gusts can lift or topple a light hutch, and temperatures can fall far below the reading your pet settled down in at dusk. A cold snap is just as unforgiving, freezing drinking water and turning damp bedding into a chill that a small body cannot warm its way out of. The plan has to be made before the weather arrives, not during it.
Bringing outdoor pets under proper cover
The most reliable option is moving the whole hutch into a shed, a garage where no vehicle will be started, or a sheltered porch ahead of the storm or freeze. Moving the hutch rather than carrying the animal to a strange cage keeps bedding, smells, and hiding places familiar on a frightening night. Check the new spot is itself dry and ventilated, set the hutch off cold concrete on wood or bricks, and settle your pet in during daylight so the first crash of thunder does not coincide with being handled.
If the hutch has to stay where it is
Turn the hutch opening away from the prevailing wind and secure a heavy waterproof cover over the roof and back, weighed or strapped down so it cannot flap or lift, while leaving a clear ventilation gap that wind cannot blow straight through. Raise the hutch off the ground if you can, add boards or bricks as a windbreak on the exposed side, and confirm the run cannot flood where it stands. A hutch sitting in a dip that collects storm water needs moving regardless of how good its cover is.
Bedding, food, and water through the cold
Pack the sleeping compartment deep with dry hay or straw so your pet can burrow right into it and build a warm nest, and replace any bedding that gets damp the same day, because wet bedding in freezing air is worse than less bedding kept dry. Offer plenty of hay to eat as well, since digesting forage helps rabbits and guinea pigs generate body heat. Check bottle spouts and bowls several times a day in a freeze, thaw or replace frozen water promptly, and remember a pet that cannot drink cannot eat properly either.
Checking through the storm, and afterwards
During the storm itself, make brief checks when it is safe for you to be outside: cover still secure, sleeping area still dry, pet moving and responsive rather than hunched and cold. Afterwards, look for a pet that is off its food, unusually quiet, or has wet fur and a cold body, and bring that animal indoors to warm gradually while you phone your veterinarian for guidance. Dividing those repeated visits helps too — KinsLe's Care Teams lets you assign the bedding change, the water-thaw rounds, and the post-storm check to named helpers for each pet, with completed tasks marked by a timestamp.