Per https://flightaware.com/live/flight/N725TH/history/20220904/2150Z/tracklog N725TH here from 462' to 900', probably sightseeing flight, last minute local time at 15:07:56 altitude 900' at 144MPH, 15:08:26 still at 900' 142MPH, 15:08:49 suddenly air speed reduced to 115MPH (?) last altitude reported at 900' and no further transponder data? Deadstick or engine problem the pilot could have easily glided the plane to a emergency water landing, the DHC-3 Otter stall speed is 58MPH? N725TH probably nose dived down in to the water at 115MPH? At 900 feet I would have lots of chance recover it if flying a Cessna 172 plane? I don't know where you saw the local weather in the vicinity of the crash, you're just speculating of windsheard, right?
All speculation but the weather conditions were there for windshear as Cliff Mass says at the end of his post. Also, the plane was actually climbing at the time of the crash from 600 to 1000 ft. and losing speed. So, if a windshear happened at just the wrong time during a climb...bad luck.
Or maybe not. That’s why the NTSB is there.
By the way here’s a video of windshear happening in Puget Sound in 2013 looking toward Whidbey Island from Kitsap. It’s pretty common in Puget Sound apparently.
http://www.youtube.com/watch?v=s0IIKWCc_9M&feature=youtu.be