Seattle Snarlcast answers one question before you grab the keys: go now, or wait? Pick a destination — and a starting point, if you want drive times — choose when, and you get a verdict (Smooth, Mixed, or Snarled), the named incidents and events behind it, a camera on the route, and the best windows to leave.
It runs on live WSDOT data — highway alerts, flow sensors, travel times, and cameras — plus the City of Seattle's permitted-event feed. Every check is timestamped, and when a feed is down the app says so instead of faking it. Save your regular drives as corridors and each one becomes a live card the moment you open the page.
Questions
What are corridors?
Saved A-to-B trips. Run a forecast with a starting point, tap "Save this corridor," and from then on the deck answers "how's the drive right now?" in one glance — verdict, minutes vs. typical, the incident by name, and a camera. Flip a card to check the other direction.
Where does the data come from?
Straight from WSDOT's Traveler Information API and data.seattle.gov's event permits. Nothing is scraped, cached overnight, or hours stale — the timestamp on every check shows exactly when it was read.
How is this different from the WSDOT app or Google Maps?
Maps gives you an ETA after you've committed to leaving; WSDOT's tools are statewide lists. Snarlcast answers the earlier question — should I go at all, and when — for the trips you repeat, and names what's actually causing the slowdown.
Which areas does it cover?
The Seattle metro. WSDOT highway data spans the region — I-5, I-90, SR-520, SR-99, I-405 — so corridors ending in Everett, Bellevue, Issaquah, or Tacoma work. The civic-event layer covers permits inside Seattle.
Why doesn't it know about a regular game or concert?
The built-in layers read public permits and highway data. Ticketed venue events come in once you add a free Ticketmaster key in settings.
Is anything stored on a server?
No. There's no server and no account. Corridors, trips, and any keys live in your browser only, per device.
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