Definitely make an appointment with a doctor to talk about your asthma. Until you do have the appointment, I'll second the scarf/balaclava thing, or look into the breath warmers for skiing and such.
I used a cheap neck gaiter last year for riding down to -5 F and didn't have any problems with my asthma.
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"There is no greater wonder than the way the face and character of a woman fit so perfectly in a man's mind, and stay there, and he could never tell you why. It just seems it was the thing he most wanted." Robert Louis Stevenson
