Autoland systems are basically designed to be used during low visibility caused by phenomena like fog, NOT for tropical downpours with or without windy conditions. Foggy conditions hardly ever go together with extreme wind conditions. (excluding Scotland...
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Autopilots most likely have insufficient authority to cope with a large and sudden wind shear or down draft because of entering a shower on short final or flare heights.
Loosing visual reference AFTER You made the decision to land is a nasty one. I one time asked our training manager to incorporate that item in a new Type recurrent. He did and it made for some interesting experiences with several crews as I heard later.