Please kindly help me with the followings. Thanks a lot!
1.
A heavy snow was falling a fine picking, whipping snow, borne forward by a swift wind in long, thin lines.

My questions:
What's the meaning of picking in this sentence?

2.
"Why, hello, Harry!" he said, addressing a lounger in one of the comfortable lobby chairs. "How are you?"
"Oh, about six and six," said the other.

My questions:
My dictionary explain the phrase about six and six as just so so - neither great nor too bad. I wonder what's story behind this phrase.

3.
With the growth of the crowd about the door came a murmur. It was not conversation, but a running comment directed at any one in general. It contained oaths and slang phrases.
"By damn, I wish they'd hurry up."
"Look at the copper watchin'."
"Maybe it ain't winter, nuther!"
"I wisht I was in Sing Sing."

My questions:
What's the meaning of the word nuther?

Question

Please kindly help me with the followings. Thanks a lot!
1. 
A heavy snow was falling a fine picking, whipping snow, borne forward by a swift wind in long, thin lines.

My questions:
What's the meaning of picking in this sentence?

2.
"Why, hello, Harry!" he said, addressing a lounger in one of the comfortable lobby chairs. "How are you?" 
"Oh, about six and six," said the other. 

My questions:
My dictionary explain the phrase about six and six as just so so - neither great nor too bad. I wonder what's story behind this phrase.

3.
With the growth of the crowd about the door came a murmur. It was not conversation, but a running comment directed at any one in general. It contained oaths and slang phrases. 
"By damn, I wish they'd hurry up." 
"Look at the copper watchin'." 
"Maybe it ain't winter, nuther!" 
"I wisht I was in Sing Sing." 

My questions:
What's the meaning of the word nuther?

Answer

My turn! :)

Picking probably means the snow was falling small but sharply - something between pecking and pricking?  Somewhat related to "pick" as in "to pick on someone".  A pick is also a sharp tool, eg. ice-pick.

"Six of one, half-dozen of the other" we often say.  One thing is same as the other.  So the phrase probably just means "so-so".

We still say "copper" for policeman here... same in the UK.  But FD is right, it's an 'old' word in the USA.  And I agree, "nuther" probably means "neither".  From the slang and oaths in the comments, I guess they were common uneducated folk, who probably wouldn't bother with clear pronunciation.  So you'd hear it said as "nuther".

Answer

Hi... yes "nuther" doesn't exist... sorry it is "neither" probably...

Answer

An alternate definition of "picking" is throwing or thrusting - in other words a windy snow that picked up lighter things and threw them. 

The story behind "six and six" is that there is no story. He is saying that nothing special has been happening to him of late. 

The last is old time slang - the use of "copper" has fallen into disuse ("cop" is still in use). So I'll have to take a guess. "nuther" is a mispronunciation of "neither". The comment would be made in response to something that is impossible. The answer would be the same as "Yeah, and the Pope's not Catholic, either!" 
It is meant to make the recipient look foolish. I get the impression that they are in the middle of winter when this is being said.