Handlebar Thermometer.

[JustPassinThru_imp]

Only problem I'd have with that...is that it's likely that if the face is in bright sunlight, you'll get an incorrect high reading.

My Suzuki Burgman and Toyota truck both have thermometers, sensory-units shielded from sun, on them...especially on a bike, it's easy to learn to...if not depend on it, consult it when dressing out. Eliminating subjective- is it really getting colder or is something else making me chilled like this?

I've seen little auto thermometers with a 20-inch sensor bulb that could be put down in shade somewhere.