Smart Switch in HOT Sun
Who cares where the smart switch is physically located?  Not the smart switch.  Put it somewhere sheltered.
If you also want manual control in that location, then select a smart-switch that's designed to retrofit into old-school 3-way switch circuits.  It will expect a plain old &quot;steam&quot; switch as its &quot;wired remote&quot;.  Fit a plain old switch here, run a (probably /2) cable to the smart switch location, and there you go.