ThermoPro TP55 Digital Hygrometer Indoor Thermometer For Winter, this ThermoPro TP55 Digital Hygrometer Indoor Thermometer ($15, originally $16) is going to be such a lifesaver. It can monitor the temperatures of up to three remote locations at once. Image Source: amazon.com ThermoPro TP55 Digital Hygrometer Indoor Thermometer $15 from amazon.com Buy Now