Cheryl,
We are all coming to your house!!! Where do you live? I live in Central Pennsylvania and the temp is hovering around 10 above zero but this does not include the windchill which I think makes it actually -14. This has been going on for several days now and will not end until Wednesday if we are lucky.
I'm a good cook and I can clean in exchange for the use of your sunny patio!!
I'm glad you came up with a solution to your warped mat problem. Thanks. Suzanne