Mountain Out: Mt. Rainier view

Is Mount Rainier out? Mountain Out tells you if you can see the mountain today from Seattle, Bellevue, Tacoma and Olympia, hour by hour for the next two days. It's free, with optional tips and no ads.

It reads the weather forecast along your line of sight (low, middle and high cloud, and fog) and gives one plain answer about visibility on the first screen: Mt. Rainier is out, partly out, hidden, or in the dark, with the reason. Clear to the summit. Low cloud between you and it. Cloud on the lower slopes. Thin high cloud over a clear mountain.

The picture is the view from your park at the size a long lens shows it: Kerry Park in Seattle, Downtown Park in Bellevue, Ruston Way in Tacoma and the Capitol Campus in Olympia. The views are illustrations of the real terrain from that spot, lit by where the sun really is. Slide the sun across the day and the light moves with it: dawn, midday, the pink alpenglow after sunset, blue hour, a moonlit night. When the forecast puts cloud or a deck on the slopes across the mountain, the picture shows it. Pinch to widen from the summit to the city beside it.

What it tells you
• Out now, or when it comes out next, hour by hour for 48 hours.
• Tonight's best light, and until when the summit stays pink after sunset.
• Why it says what it says: your line of sight to the summit, side on, with the forecast's cloud drawn where it sits along it.
• From where you are, anywhere in Washington: it traces your own line of sight to Rainier over the real ground. If a hill is in the way, it names the hill and the nearest park that clears it.
• One notice when the mountain is due out, only if you ask for it.
• Share the view on your screen with one line saying what's out.

How often it's right
We haven't tested how often this forecast is right yet, and sunset light isn't checked either. The app says so under Why.

Private by design
No accounts, no ads, no analytics. Your location is used only to draw your view, and your exact location never leaves your phone. The forecast service gets a point rounded to about 2 km, and the ground map for your own spot downloads the area around you.

Mountain Out is free. If it helps you see the mountain, there's an optional tip in the Why sheet. A tip changes nothing in the app.

Forecast data from MET Norway (CC BY 4.0). Ground from AWS Terrain Tiles (https://registry.opendata.aws/terrain-tiles/): United States 3DEP (formerly NED) and global GMTED2010 and SRTM terrain data courtesy of the U.S. Geological Survey (https://www.usgs.gov/). Places © OpenStreetMap contributors.

Not a government app; it is not affiliated with the U.S. Geological Survey.

Recent changes:
Mountain Out now has a home screen widget. It says if Rainier is out and until when, or when it should come out next, from the forecast the app already keeps, so it uses no extra data. Add it from Why, or from your phone's widget list.

Why now also says how often "Rainier is out" turned out right when we checked it against the Space Needle camera.