It was hot as hell in Cyberia. The otherwise ultra cool, stylishly minimalist cafe in London’s West End heaved with adolescent bodies huddled over a bank of computers. The concentration was so intense you could hear a microchip drop. These 14-year-old boys and girls were bravely launching into the vast realms of Cyberspace, via the much-vaunted, hysterically-hyped Internet.

But hang on a minute. What they’re doing looks kind of, well, boring. Painstakingly, they key in conversations to counterparts in Cape Town, Johannesburg and Kuwait City and then wait for the space-lagged reply. “Has Johannesburg got a decent soccer team?” asks one of two boys who have logged on as Cyberia 1 to the intriguingly named Buggerlug in South Africa. In the meantime, dorky Herman from God knows where butts in with “How’s the weather in London today?” Cyber shmyber.

Here are kids on opposite ends of the Earth communicating with each other on the global superhighway and all they think to say to each other is “Stefan Schwartz is COOL!” (Schwartz plays for Arsenal and, if you’re a north Londoner, you may agree he’s got talent) and “Cape Town’s cold and rainy today. How’s London?”

But that, in a way, is the point of the exercise. These dozen teenagers were at Cyberia for the launch of Weather Eye, a book about teenagers, the Internet and the weather. Not the traditional polite English neurosis about the weather, but the New Weather, chaotic, out of control, showing us irresponsible earthlings a thing or two about what happens when you abuse your planet.

Author Lesley Howarth is neither a teenager, a ‘Net nerd nor a meteorologist. She is, rather, a glamorous mother of three whose ear for youthful dialogue, love of adventure and astuteness about young people’s concerns has made her a successful children’s book writer. Last year she won the Guardian Children’s Fiction Award 1995 for MapHead, the story of a young visitor from the other-earthly Subtle World who comes to our world to look for his mother.

Weather Eye is a very different book, rooted in the last year of this millenium. Set in the rural Cornwall where Howarth and her family live (in an energy-efficient home built, yes built, with the sweat of their own respective brows, by her and her computer manager husband), it is the story of a teenage girl called Telly. This is no ordinary kid. She lives on a wind farm with her parents, she’s a member of a group of young people from all over the world who swap information about the dramatic climactic changes happening everywhere. And she has suddenly developed psychic powers since having a near-death experience after a serious blow to the head by a wind turbine during a ferocious storm. Like Nostradamus, she is able to see into the future.

Heavy stuff, dealing with the effects of global warming, taking a position of international leadership on the Internet and knowing the exact date of everyone’s death. But while there are credible smatterings of techno talk (what buttons to press to get into the Net) and weather jargon (verbatim sections from the shipping forecast, as incomprehensible as in real life), the book is really about Telly, her responses to the events and people around her and her determination to take control in some way of the chaos raging without.

She is aided, abetted and hindered by a colourful assortment of incompetent boys, a gauche girl and, most importantly, her barely tolerated eight-year-old brother. Race, like all little brothers, is a thorn in his sister’s side as well as her greatest admirer, a creature whose favourite hobby is making realistic dog messes from coffee grounds (filter, not instant) and then carefully, even lovingly, coiling them in places chosen to cause the most consternation. Telly and Race’s realistic exchanges of absurdist, ephithet-strewn venom, undercut with intimacy, are a joy to behold.

For Howarth, the scientifictechnological themes represented “a challenge - to write a book about environmental issues that is positive. My own kids are deeply anxious about what’s happening to our climate. That’s why I wrote this. I don’t see why children’s literature shouldn’t be topical and challenging. There are risks you take in doing it but they pay off.”

In making the hero of a story about the Internet a girl, was she consciously creating a positive role model for girls that challenged stereotypes about female technophobia? Lesley Howarth has no truck with such notions. “I feel deeply non-sexist about this. There should never be a question that the Net is women’s intellectual property. Of course it is. The only way to leave sexism behind is to forget about it. I find it profoundly depressing for people to go on about IT being male dominated. It’s very negative and passe. It’s up to women and girls to take the initiative with technology. We need to stop moaning.”

The former market gardener, cook, and care assistant was drawn to computers when she decided to start writing and to the Net “because the idea of it intellectually excited me, the liberation of it, the fact that there are no boundaries”. She openly admits that she wouldn’t have got on to the Internet without her husband, who rigged the thing up for her. Now it is at her disposal - and at her daughters’, who regularly spend time on a chat line with young people from Europe and America.

Howarth’s next book is a novel set in the Stone Age. No technology; no science. Plenty of perks, though, for the writer. “After the serious ideas in Weather Eye I wanted to set something so far back in the past that I could invent anything: there’d be no research, no having to carefully locate school holidays in the plot.” You get the distinct feeling that this is not laziness but a desire to delve into playfulness - and to knock back a few more boundaries.

* Weather Eye, published by Walker Books, Pounds 8.99, will be reviewed by Gillian Cross in The TES later this month.