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Both Visual Studio (from Microsoft) and WebStorm (from JetBrains) give you JS intellisense. Granted, JS intellesense is never going to give you as much information as a statically typed language, but Typescript helps the editor as does comment type-hinting in VS (using something along the lines of JSDoc)

You can annotate types within JSDoc, which can help somewhat. But granted, compared to statically typed languages it's still a clusterfuck. Currently writing documentation comment translation for a C#→Java/JS compiler and I'm injecting as much type-system metadata as I can, but IDE and editors still disagree to what extent they're actually using that.

Facebook made flow https://github.com/facebook/flow and TypeScript has already been mentioned

related: look into http://ternjs.net/

Use typescript. I think it will solve a lot of your issues and also give you a basic sanity check

+1 for JetBrains IDE's with JSDoc (IntelliJ here)