01/03/2018 Newsround

Hi, I'm Ricky with your Newsround

update for this morning.

Coming up...

Who are you dressing up as?

Some top authors tell

us their World Book Day ideas.

Hi, everyone, Tom Fletcher here.

Hope you're having

a great World Book Day.

But first, the big freeze continues

with many of you waking up

to more snow this morning.

Scotland has seen the worst of it.

The most severe weather warning

is still in place there.

Travel has been disrupted for many -

we're hearing that some people have

been stuck on the roads all night.

But lots of you are

enjoying the weather.

Teachers and students at a school

in Essex had a snowball

fight on a epic scale -

take a look at this.

DRAMATIC MUSIC

Go!

LAUGHTER

DRAMATIC MUSIC

The headteacher at that school is

called Mr Snow, I kid you not!

It's not just the snow that makes

you feel cold on days like today -

there's also something called

the wind chill factor.

Sounds interesting.

So what is it?

It is absolutely freezing

at the moment but did you know

that the temperature we feel

is different to the actual

temperature of the air around us?

Now, outside the studios

here at newsround it says it's

around -1 degree but it also

says it feels like -7.

Now, that's because of something

called the wind-chill factor.

Weather experts often call

wind-chill of the feels

like temperature.

It's worked out using the air

temperature, humidity,

that's how much water vapour

is in the air, and wind speeds.

All this information is combined

into the science of how heat is lost

from the human body.

So, on a cold, windy day like today,

why does it feel even

colder than it really is?

On a calm day, our

bodies insulate us.

we give off heat so we warm

the air around us.

It's a bit like having a warm force

field or blanket.Bbut

But when it's cold and windy,

the wind hits the face and called

the skin to almost the same

temperature as the air.

It essentially blows the blanket

away so we feel much colder.

So, there you have it, wind-chill.

Pretty cool, eh?

It's so windy!

Help!

Next - happy World Book Day!

Lots of you are dressing up today.

But which characters

would famous authors like to be?

They've been telling us.

If I had to dress up

for World Book Day, I have one hero,

a writer and an actor,

William Shakespeare.

I think he's absolutely brilliant

and I would love to wear those big

baggy trousers and tights.

For World Book Day, I'm

dressing up as Harry Potter

with his invisibility cloak.

It's the easiest costume.

It looks like this.

I dressed up as the amazing late,

great Louise Rennison's Georgia

from Angus, Thongs And Perfect

Snogging.

So I dressed up as a huge

stuffed olive and I walked

up and down my street.

One of my favourite characters

is Ratty from Wind In The Willows

because I love the fact he's always

in his little rowing boat,

so I'd quite like to be in a little

rowing boatdressed as Ratty

and reading a book

on World Book Day.

I think I'd probably dressed up

as Matilda simply because,

as far as I can remember,

she always had an armful of books

and I think that's the best way

to go out into the world,

so I'd probably pick her.

I think it would probably be

Batman because Batman

was my all-time hero and probably

is still my all-time hero.

If I could dress up as anyone -

is it supposed to be

someone from a book?

I think so, yes.

Someone must have written a book

about Elizabeth Taylor.

I could dress up as Elizabeth

Taylor, couldn't I?

We can't --

We can't wait to find out who you're

dressing up as today.

Head online to let us

know and send us a snap!

And we'll have two top authors live

here in the studio in half an hour -