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 in Washington State, 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.
• At night, whether it should come out the next day, and when.
• Tonight's best light, and how long the summit can stay 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 State: it traces your own line of sight to Rainier over the real ground. If a hill is in the way, it says so, names the hill when it can, and points you to a nearby park that clears it when there is one.
• 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
Rainier's forecast has been checked in a small test against the Space Needle camera, and the app's Why sheet shows how often it was right.

Private by design
No accounts, no ads, no analytics of ours. Your location is used only to draw your view, and the app never sends your exact location anywhere. 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.