Clara Sky app icon

Clara Sky

Weather · Mac & iPhone

A weather app with an actual meteorologist in it. Clara reads what the forecasters at your local National Weather Service office wrote this morning, and tells you what it means for your afternoon.

iPhone & iPad

Get it on the App Store

Free · iOS 17 or later

Mac

Download for macOS

Free · macOS 14 or later

Version 1.1.1 · Needs your own Anthropic API key — see below

01 Why this one is different

Every other weather app shows you a number a computer model spat out. Nobody looked at it. Nobody knows that fog sits in your valley until ten, or that storms usually fall apart before they cross the ridge.

Several times a day, meteorologists at your regional National Weather Service office publish a Forecast Discussion — their own reasoning, in their own words. Which model they trust today and which one they think is wrong. How confident they are. What could go wrong. It's the closest thing there is to a forecaster's notebook, and almost nobody outside the field ever reads it, because it's written by meteorologists for meteorologists.

Clara reads it. She folds in severe-storm outlooks, any active alerts, and — if you switch it on — recent weather coverage from your area, then translates the whole lot into plain language.

So instead of “60%,” you get to hear why it's 60%, when it changes, and whether you'll want that jacket.

02 On air
The Briefing: Clara's forecast written in her own voice above the current conditions
The Briefing — a short forecast in Clara's voice, ready when you open the app.
Ask Clara answering a question about whether it is safe to go outside
Ask Clara anything, in your own words. Answers come from real data for your exact spot.
Two National Weather Service alert banners above the current conditions
Active National Weather Service alerts, as unmissable broadcast banners.
Next-hour rain timing strip with an hourly forecast below
Next-hour rain timing, plus the hourly strip and a TV-style 7-day outlook.
Clara Sky's introduction screen explaining The Briefing, Ask Clara and severe weather
Clara introduces herself on first launch, and explains what she's actually doing.
Clara Sky's biography describing her as a meteorologist who reads model runs for fun
She reads model runs for fun and celebrates when a forecast busts. That's how you learn.
03 Weather School

Clara is a weather nerd and it shows. Tap the mortarboard and she'll explain what a “40% chance of rain” actually means — it isn't what most people think — why “scattered showers” is an honest answer rather than a hedge, why a July pop-up storm is the hardest call she makes, and when your radar screen is quietly lying to you.

There's an interactive demo in there showing how two completely different afternoons produce the very same number on your phone. Nothing is dumbed down; she assumes you can handle it.

Weather School opening screen with Clara's portrait and the first lesson Interactive demo showing probability of precipitation as confidence multiplied by coverage
04 On the Mac too
Clara Sky on macOS showing alerts, current conditions, the hourly forecast and Clara's briefing side by side
05 What's in it

Two honest caveats

Clara runs on your own Anthropic API key. It's free to create, and usage is billed by Anthropic to your account — typically pennies a day. Without a key the forecast still works in full; you just won't hear Clara's voice. There's no subscription here and nothing to buy from me.

The local-forecaster layer is US-only. Forecast discussions and alerts come from the US National Weather Service, so that's where it exists. Everywhere else, Clara briefs you from worldwide forecast data in the same voice.

Forecast data by Open-Meteo (CC BY 4.0). US alerts and forecast discussions from the National Weather Service. Severe outlooks from the NOAA Storm Prediction Center. Next-hour precipitation from  Weather.

iPhone & iPad

Get it on the App Store

Free · iOS 17 or later

Mac

Download for macOS

Free · macOS 14 or later