It is dumping in San Diego today! That never happens! It is usually ideal conditions for install. But it is important to treat extreme conditions appropriately. It is the responsibility of the installation crew to not install when it is too hot or humid or too cold. The flooring will not acclimate correctly and the floor can move after conditions go back to normal. It is ok to install during the rain as long as you are careful to keep the wood dry. A great way to avoid the mess of cutting outside and tracking in wet on to your new floor is to construct a zip wall room inside the house that will contain the dust. This is also an option in a condo building where you do not have access to a patio or aren’t allowed to cut on it. These are the extra precautions your installers should be taking to make sure to keep your home clean and your flooring install successful.