Over the last week I have been asked the question can I leave my above ground pool empty over the winter? The answer is always NO.
Above ground pools need the weight of the water in them to provide an optimal level of stability. Without water supporting the wall you run the risk of the pool wall coming out of the track. Also without water in the pool the liner can shrink and no longer fit your pool.
The most common method to winterize an above ground pool is to add the appropriate winterizing chemicals, lower the water level to just below the skimmer and return, cover the pool and remove all equipment plugs. Of course with rainfall water tends to collect on top of the cover causing it to sag. You will want to keep this rain water pumped off the cover. Other options are available to prevent having to drop the water level such as placing a gizzmo in the skimmer or installing a skimmer door and installing a plug in the return.
The bottom line is never leave your above ground pool sitting empty for any extended period of time.