@BigApple, Buy one of these controllers, and be sure to get at least 20% off or go to close the page and get the Make an Offer.
Digital Heating and Cooling Professional Thermostat Controller -40-176°F 15A/1875W BN-LINK
but before you buy one, read my post over here on how to set it up. https://www.thcfarmer.com/threads/how-do-you-control-a-heater-and-exaust-fan-in-your-tent-which-controller.145078/
In my tents, with a cold intake/outside temp differance of more than about 20-25* between my tents inside temp (75-80*) and the ouside intake air (50-60*), I have issues with condensation on the inside of the tent and humidity getting into the 80% range. Not good. You said your intake air was as low as 30’s*-40’s* and we want our tent in the upper 70’s* to lower 80’s* so yes, you might expect to be needing/running a dehumidifier inside the tent.
Feel free to ask me any questions about getting it setup and hope that helps.