weather for seattle.

Cool Pacific sea-surface temperatures (48–55°F) suppress convection while persistent onshore flow drives a marine layer over the Puget Sound. The layer resists daytime heating until the high sun angle of late June begins to break it down, producing roughly 200 days of measurable cloud cover per year.

Drizzle forms when cloud droplets coalesce slowly under stable, cool air with minimal updraft activity — typical of Seattle’s winter pattern. True rain requires a more active cumulus column, which only develops during frontal passages or unusually warm, moist incursions from the southwest.

The rain shadow has its strongest effect during southwesterly Pacific flow. Sequim and the northern Kitsap peninsula sit at the shadow’s center and receive only ~16 inches of rain per year, while Seattle proper averages ~38 inches — about half of what Forks and the western Olympic Peninsula get.

Vesper replaces template-driven forecasts with short editorial briefs written in an authorial voice, and publicly grades its own sunset predictions through Sunset Verify. Every other weather app on the market generates its text by filling variables into a template. Vesper writes each forecast as original prose with a point of view about the day.

Vesper is free to download with core weather features. Premium features and pricing will be announced at launch.

Sunset Verify is Vesper's signature feature that predicts sunset quality each day from live atmospheric data and lets users verify the prediction with a photo, building a personal accuracy track record over time.

Vesper is currently in beta. Join the waitlist at vespersky.ai/beta to get early access and be notified when the app launches on iOS and Android.

An editorial weather app applies a point of view to the same atmospheric data every other app has. Instead of showing you a grid of numbers, it writes a short brief — two or three sentences with intent — about what the day is going to feel like and what you should probably do about it. The data is identical. The voice is the product.

Vesper's briefs are generated by a language model operating under an editorial style guide written by people and refined through thousands of examples. The style guide, cut discipline, and voice rules are the content. The model is the mechanism. Template weather apps are generated by models that were never given an editorial style guide, which is why they all sound identical.

Vesper does not ship radar maps or a proprietary severe weather alert system. Severe weather alerts come through the operating system, which is the right place for them. Radar was rejected because a radar map is not a brief and would not make the forecast more worth reading. We respect both as product decisions. We are doing something different.

Vesper publishes editorial weather coverage for over 100 US cities with full daily briefs and all 50 state hubs with region-specific editorial context. The mobile app gives you a brief wherever you are — anywhere Vesper has weather data coverage, which is essentially every populated area in the world.

Yes. Vesper uses your approximate location only to deliver weather forecasts for your area. Location data is not stored on our servers, not sold, and not shared with third parties. Photos taken through Sunset Verify stay on your device and never leave your phone.

A fresh editorial brief is generated every morning based on that day’s forecast. Inside the app, live conditions update continuously based on your location. The editorial brief is a once-a-day artifact — written to be read in the morning, not refreshed hourly.

Yes. Vesper does not require an account to read the daily brief, check sunset predictions, or use the editorial features. Personal data like Sunset Verify history is stored locally on your device, so there is no cloud account to create.