For Seattle I wouldn’t worry too much about heat-related degradation, and that’s the biggest concern when getting a 30 kWH model (which all 2016 SV and SL cars have). You can get the “old” style 24 kWH battery with the Leaf S but I don’t recommend it for your climate as its heater uses up more energy than the heat pump of the more expensive trim levels.
Blue Ocean 2012 Leaf SV, lost that 1st bar at 34 months/26,435 miles. Lease returned 2 months later. Final LeafStat figures: 225 Gids, 17.44 kWH, SOC 91.89%, SOH 82.36%, 69.49% HX, 54.57 Ahr, battery temp 61.8 F.
Now driving a 2015 VW eGolf SEL.