Could be caused by a couple of things. If you have an onsite septic system (tank and drain field) the tank may be full, and the rainwater is causing it's contents to backup the main drain back in to the house. A vent pipe could be plugged, which causes the sewer gas to back up. If you are hooked to a public sewer, there may be a blockage in the main drain out to the line in the street. Have a Plumbing contractor check it out. It can be very dangerous.
I would wonder if there is a break or blockage in the sewage pipe line.
May be the floor drain in the laundry room is without Trap..
When it rains, the rainwater mixes with trash and other pollutants and it is carried down our storm drains and into our oceans. Gasoline and sewage spills from boats and ships also contribute to the pollution problems. Also if people do not clean up there trash and just leave it into our community then when it rains, the rain picks up all the trash and then goes into sewer drains, and the sewer drains lead to the ocean.
You should have the smell of suffer checked out with gas detecting equipment because there is a possibility you are smelling deadly H2S gas
the rains
when it rains it snows
It is still just a basement.
ummmmm............. your not supposed to i suggest you get that checked!!
Sounds like the trap in the sink is getting the water pulled out of it. It probably wasn't vented properly.
Most likely a drain has dried out and there is no water in the trap to stop the gas from coming up. Sink, shower, or main floor drain.
You hire a plumber to put in a one way sewer drain valve.
Awful.
Awful.
Install a one way check valve in the line from the house to the sewer.
Either they are on a separate sewer line and connect to the main sewer line later on or they sewerage is pumped by means of a machine into the main sewer line.
The trap in the drain line under the sink is dry. It should have water in it to stop the smell
Lime
Frozen sewer out side
There are details you didn't give us.If your washroom floor drain only clogs when it rains, that may be a feature, not a bug. There are backflow traps that can be installed in floor drains to keep them from backing up and getting sewer water all over the floor. If your washroom floor is in the basement, the fact that it's clogging when it rains may be saving you from a big, nasty cleanup job.