2003 Mazda Tribute Engine light is on Engine misfire

Engine Performance problem
2003 Mazda Tribute 6 cyl Four Wheel Drive Automatic

Recently within the past 2 months, when it rained or got humid, the engine had misfired a couple of times after starting the engine and driving. The problem would go away after about 15 - 20 mins. Then it would run fine.

However yesterday I had the same problem, it had just finished raining and the engine started to misfire after turning it on, but this time after about 20 mins of driving, the Engine light came on. Not flashing, just a solid light.

I checked the gas cap, to make sure it was properly secured, and there was 1/2 tank of fuel in the car. Not premium, but I had put premium in the past after the first time it happened. The engine did misfire once after I put premium gas, but the issue went away for a couple of weeks.

However today I turned on the engine and the light stayed on, but the engine did not misfire, it ran fine.

Before I take it to a garage and get hit with an exhorbitant price, are there any suggestions as to what may cause this? Also if the engine seems to be running fine, can I still drive with it for a while before I take it to a garage