Mode · Offline & Reliability

Offline mode

AlaskaTides is designed for Alaska's no-signal coastlines. This page documents what gets cached, how long it lasts, and how to pre-load 7-day tide windows for key stations before you leave coverage.

Tide predictions
7 days
Cached at load time
Station data
Persistent
Stored in service worker
Marine forecasts
1 fetch
Cached on last view
Map tiles
Partial
Base layer only
What gets cached
Tide predictions
7 days
Per station · MLLW-referenced
Loaded at first visit, refreshed in background when online
Station info
All 509
Names, IDs, coordinates, type
Baked into the app bundle — no fetch required
App shell
Full
HTML + CSS + JS
Service worker pre-caches on install — works on first offline load
Live observations
Not cached
Requires network
Buoy data, water temp, and wind require a live connection
How to prepare for no-signal areas

Before heading to remote coastlines: load the home page for each station you plan to use, wait for the tide chart to populate, then leave the device on. The service worker will cache predictions in the background. AlaskaTides aims to function fully for tide viewing with zero network.

Settings (units, pins) → ← All modes