Usually when a flight is delayed or cancelled because of weather compensation is not given. If you got a voucher because of weather enjoy it's not normal to get a voucher since southwest can't control the weather.
If your flight is cancelled due to weather hotels are not usually provided. On occasion they will give a discounted hotel voucher but usually the only time a hotel is given as compensation is when a maintenance cancellation happens and the airline can't get you out till the next day.
If you are wanting compensation for a delay you will need to Contact Customer Relations.