What is the tone of the story in the beginning?

The early tone of Shirley Jackson's "The Lottery" is light, fun, and peaceful.  Jackson's opening sentence tells readers that the weather was perfect.  

The morning of June 27th was clear and sunny, with the fresh warmth of a full-summer day; the flowers were blossoming profusely and the grass was richly green.

That's "go outside and play some catch" weather.  It makes you think of packing a basket of food, taking a blanket, and having...

The early tone of Shirley Jackson's "The Lottery" is light, fun, and peaceful.  Jackson's opening sentence tells readers that the weather was perfect.  

The morning of June 27th was clear and sunny, with the fresh warmth of a full-summer day; the flowers were blossoming profusely and the grass was richly green.

That's "go outside and play some catch" weather.  It makes you think of packing a basket of food, taking a blanket, and having a picnic.  That single sentence likely brings a smile to most readers faces, especially readers who have been dealing with winter for a few months.  

The light and fun tone continues for quite a few more paragraphs.  Jackson tells her readers that the townspeople were gathering together in the town square.  Children arrived first and began to play and run around.

 . . . they tended to gather together quietly for a while before they broke into boisterous play, . . . 

The adults were also portrayed as stress free.  The men gathered together and made small talk of the spring planting and the women gossiped to each other.  Everything about the lottery proceedings is portrayed as a fun, town festival type event.

The lottery was conducted--as were the square dances, the teen club, the Halloween program--by Mr. Summers. . . 

 It seems completely peaceful, which is why the story's violent ending is so shocking. It completely doesn't fit the initial tone.