I hope you really want the dog and will keep it whether the dog "gets it" or not.
Going to 2nd what Joan said...you DO want a dog you can take proper care of and will treat it well and play with it, get shots, health care, etc? Also get it neutered or spayed? Dogs are pack animals and really don't like being outside all the time, they also love human interaction each day too.
I have suffered from severe allergies all of my life, I have been on medication to control it and have now had asthma induced allergies. I have 4 horses, my chicken flock and an aged Siberian Husky who sleeps with us some of the night and will jump on the bed in the morning to say hello. I really hate to see people who say they have such severe allergies get living, breathing, feeling animals, only to throw them outside to live in loneliness because they don't want to work around their medical condition and deal with it and take proper care of said animal.