My Fairweather worldwide database has over 81,000 entries, many of which are available for exploration. I am registered as the only Fairweather representative at the Guild of One-Name studies. You can email me at fairweather@one-name.org  - I am member # 4856 at https://one-name.org/

 https://one-name.org/name_profile/fairweather/

Whenever you search for your Fairweather/Fayerweather relatives, you will find you get fewer duplicates if you search instead for their mother or spouse or an unusual first name, like Daedalus!

https://www.familysearch.org/ark:/61903/2:2:7569-XGN

Thanks to a special agreement between the Guild of One-Name Studies  and Family Search, the database provides extensive information, serving as a foundation for further research. Go to https://www.familysearch.org and sign in (free) then look for the category Search in this menu: Family Tree    Search    Memories     Get Involved    Activities

In that drop-down menu, find Genealogies

https://www.familysearch.org/search/genealogies

Look for the collection  Guild of One-Name Studies.

 I usually have two versions of my research available to search there. The older of the two is just a back-up and the most recent one has the latest version. 

I have made a hobby of "collecting" Fairweathers and several  variants of the name. When I first became interested in family history, in the mid 1990's, I found that there was little on the web which included Fairweathers worldwide. So I decided to start a database which I posted on Rootsweb's World Connect. I continued looking and spent a lot of time "trolling for Fairweathers". (Trolling is a type of fishing). My version was to keep putting Fairweather into the search box on my browser, following up on the "hits" and recording everything in my Reunion database. When I say that my database has over 81,000 entries, that means the entries range from extensive to one little bit of information.  Some connect to very large trees and have sources and notes. I made some decisions about how I would handle the One-Name study. To make it easier to find people, I listed people as Fairweather, even though the person's name was Fayerweather or another variant of the surname. I kept my notes and sources off the internet, unless I had complete confidence in the data & sources. I didn't allow people to download my tree - I asked that they contact me and share information.

Another place where I have some of my information is at the free site Wikitree.com. Their goal is to create one world family tree. To make that work, you may be asked to combine two profiles if they represent the same person. The rules for that website ask that information be well sourced and the entries require a lot more information, so not all my database of over 81,000 Fairweather entries will be there yet. If your family is there, please feel free to add and edit the information. If you want to be the profile manager, you can add yourself and take it over or be a co-manager with me. I am trying to add helpful information that has some solid sources so the information will be available for future generations. That's at https://www.wikitree.com/.

There is a Y-DNA study of all Fairweathers through Family Tree DNA. Anyone can join the Fairweather project there and have their DNA tested and added to the research. You have control over the privacy level of the results.  You can also add your results from some other DNA companies. The Family Finder test is autosomal, similar to the ones offered by other companies. As far as I know, the Y-DNA test at FTDNA is the only one offering tests for the Y-DNA. 

Y-DNA can only be held by males and will lead back from father to son. You may find that your relatives are one of the many families where the Y-DNA test shows that somewhere in the past, there was a boy whose last name was Fairweather who had a father that wasn't genetically a Fairweather.

So far, we know that the two main groups are Scottish or English in origin.

https://www.familytreedna.com/groups/fairweather/about