One of the first things we notice in the mornings is the weather. How many of those first tweets go something like this:
‘Brrr – cold as I crawl out of  bed – not LOL’
‘The sun. At last. Damn, I have to go to work.’
‘DH now in garden shed building an ark. Blasted rain!’

We even report average weather:
‘Nice and sunny here, a bit overcast but OK. What are you up to today?’

Some primeval instinct drives us to orientate ourselves in the day the minute we’re awake. Cave man asked whether it was a good day for hunting, gathering or beating the crap out of the neighbouring tribe. Today, we look out of the window and wonder whether the car will start in the damp, if the heatwave will continue or the delivery person won’t appear because the snow’s too deep.

We need weather to frame our lives. And so do our characters, but not in a nice way. They need disruption.

Firstly, a writer can use weather to add weight, obstacles and trouble to a character’s dilemma.  Weather can change the plot: snow falling might stop planes flying, bring down power lines, prevent a vital meeting or elopement. Prolonged, heavy rain may cause flooding,  damage to vital papers, trapping a character in a cave or cellar or a beloved pet drowning.

Weather can affect a character’s mood: sun generally cheers people up and rain depresses them. Wind is well-known for, er, winding people up. Any teacher will confirm that kids become more jittery and argumentative if there’s a gale blowing outside.

And thirdly, using weather to reflect inner turmoil adds a layer to the story: character C is waiting for character D and the meeting is going to be difficult, C paces around, fidgets, keeps looking out of the window, his stomach is queasy. The wind outside is blowing rubbish down the street and the sky is getting blacker by the minute…

How to write weather
The key is to integrate weather into the story as it affects the character at that point. I write thrillers and the reason I might describe weak winter sunlight, or perish the thought, a sunset, is that the horizontal light gets into the hero’s eyes and blinds him when he’s taking a vital shot.

Some less extreme ways to introduce environmental conflict into a scene could be:

• If teenagers are meeting anywhere outside on a first date, make it rain;
• If a woman takes her young grandson sailing, a squall blows in;
• If a man is afraid of the dark, make it a moonless night, preferably in the country, either windy or raining. Possibly both.

While weather is a vital ingredient, you only need to mention it once and the reader will set the scene themselves:

• We ate quickly, ignoring the rising heat from the afternoon sun.
• Next morning, it was still snowing and she’d left her boots in the car.
• I wasn’t surprised to see him an hour later. He came in through the service entrance, shaking rain from his umbrella.

The reader can then take their experience of rain/snow/scorching heat and use it to ‘see’ the scene in the book. If it’s rain, some readers will imagine heavy rain, others a drizzle, but it doesn’t matter. The precise nature of the rain isn’t important – all you need to do is mention the wet stuff and the reader’s imagination will do the rest.