Bear with us here for a moment, set aside your pragmatic sensibilities, and check out the Cryoscope concept by Robb Godshaw. It's a fascinating piece of technology which communicates the weather forecast in a tangible sense, the all-aluminum cube heated or cooled to the exact temperature fetched from online weather data!
The neutral state of the cube is about 85°F(30°C), which is perceived as neutral by the skin. The cube is then adjusted by the number of degrees that forecast differs from typical room temperature(73°F/23°C).
Admittedly, the Cryoscope is one of those wonderfully inventive, conceptual creations which likely will be a one-off exploration. But at least with smartphones and desktop apps, you can get both data and visual feedback about the weather at a glance right now, complete with pretty impressive animations making it clear whether a scarf or jacket is necessary:
Oregon Scientific's BA900 Crystal Weather Forecast Station offered a low-tech hardware solution (laser etched floating icons illuminated via LED like those clear paperweights available at gift shops), but it appears the device is now only available via eBay. Seems like an idea waiting to be revitalized with a higher tech finish by the minds over at Art. Lebedev Studio, and a lot cooler looking than most weather forecast clocks.