Lewis and Clarke's Big Mistake?

In December 1805, after making the first transcontinental land crossing by white man, Lewis and Clark decided to overwinter at a location south of present day Astoria (see letter A on map).

They called their collection of log buildings, Fort Clatsop, and remained there until late March 1806 (see artist rendering).

Unfortunately, they learned rapidly that they had picked one of wettest, dampest lowland places in North America, with plenty of wind to make things even more unpleasant  They were miserable, as their comments on December 16, 1805 made clear: 

 "The rain continues, with Tremendious gusts of wind. The winds violent.   Trees falling in every direction, whorl winds, with gusts of rain.    Hail & Thunder, This kind of weather lasted all day, Certainly one of the worst days that ever was!" 

Frequent comments included: "we are all wet and disagreeable," "cold and a dreadful day," and, "the rain continued as usual" 

If only they had a meteorologist with them!  Consider the Oregon annual rainfall map (see image).  They had camped in a location that receives about 100 inches a year, most of it falling during the midwinter period in which they camped.  Not a good choice.  If only they had made camp near Portland, they could have found a location with roughly a third as much rain, and considerably less wind. 

Of the 106 days the Corps of Discovery spent on the coast only twelve were free of rain and only six were sunny.   I suspect they knew they had picked a very wet location, but wanted to be near the ocean where they would have a chance to interact with a passing ship.  Perhaps they hoped for a ride to Hawaii.

And one more thing:  only a few miles from Fort Clatsop there is Cape Disappointment, the foggiest location in the lower 48 states, with 106 days of heavy fog a year.  So they were wet, fogged in, and we haven't have talked about the strong winter winds of the area.  Not your winter vacation spot.

Typical (foggy) conditions at Cape Disappointment