Usage:

At the top of the screen you can see current weather condition for the selected location.
The graphs show the weather from the current hour and 36 hours in to the future from left to right.
Select a location by clicking on the map, or by typing cordinates manually and clicking select.
The map centers to the selected location when the page load or "Select" is clicked.
Click "Save to URL" to reload the page with the location in the URL to make a bookmark or make a link.

Downloadable HTML+JS (GPLv3) version here.