The Farm at Lane's End Chapter 30

Jean is getting ready to go out - The Farm at Lane's End is the ongoing story of a typical English farming family. Farmer Ken, his wife Jean, and their son Dave. In chapter 30, Jean is getting ready to go out. Vocabulary -To wrap up means to put on very warm clothes.
Brass monkey weather is a coloquial expression that means extremely cold weather.
Treacherous means conditions that hide hidden dangers.
It's bound to be means something that is certain.
Words you might need to check - mittens, scarf, wooly hat, underfoot.
And, now to our story. The Farm at Lane's End. Chapter 30
Jean is getting ready to go out. She's going to the chemist's in the village. Ken is giving her some advice.
You'll need to wrap up, Jean. It's very, very cold outside. You'll definately need your thick wooly hat to keep your ears covered and your mittens to keep your hands warm.
Just then, Dave comes in. He's been feeding the pigs.
I say, mum and dad, it's freezing outside. I can hardly feel my fingers. It's brass monkey weather.
Jean asks Dave about the conditions outside.
Dave, is it slippery underfoot? Is it icy?
It's very, very icy mum. If I were you, I would wear the warm winter boots that dad gave you for Christmas. There's black ice everywhere. The last thing we want is you breaking a leg. We'd have to do the cooking and cleaning ourselves. That'd be terrible.
I promise to be careful, boys. I say, has anyone seen my car keys? I can't find them anywhere. I can't remember where I put them.
If I were you, Jean, I'd take the Jeep. The roads are bound to be treacherous. As Dave said, there's black ice everywhere.
How long will you be gone, mum?
Not very long, Dave. I'm only going to the chemist's. I'll be back before lunch.
Drive safely, mum. See you later.
Bye Dave, bye Ken.
Questions - Please describe the weather. Which month is it? Is it summer or autumn? Is it brass kangeroo weather? Why should Jean wrap up well? Did Ken advise Jean to wear gloves or mittens? What did Dave say about the conditions? Why did Ken suggest that Jean takes the Jeep? How do you understand the word treacherous? How do you understand the phrase "it's bound to be"? Why is black ice treacherous? Why did Jean go to the village?