ryno saidOn and off for the past few years; I do have allergies, but can't tell if it's connected or not.
Post nasal drip caused by allergies could be a cause of sore throat, as already mentioned. Being seasonal during the periods when airborne allergens are highest could be a clue. Enter your ZIP code here:http://www.weather.com/activities/health/allergies/index.html
There are also indoor allergens, an issue in Minnesota where many homes & businesses are built nearly air-tight against the winter cold. Minnesota also has a problem with indoor mold because of the climate, and many people are allergic to the spores. The site above will also link you to info on indoor allergens.
A doctor should look at your throat, and possibly take a swab to culture. You may have a chronic tonsil infection, which will flare up from time to time. The doctor can also see if you've got post nasal drip, from allergies or another cause. Something topical like a lozenge can help the symptoms, or even drinking tea without cream, but will not cure it. You should find out the actual cause so it can be treated.