I’ve finally added outside temperature monitoring for my garden deep bed using a Wemos D1 Mini I got some time ago. The reason is for checking the temperature of the soil for planting soon. The project uses a DS18B20 1-wire probe for earth temperature monitoring AND a discrete DS18B20 for the ambient air temperature. Using battery pack with three 1.5V batteries, the ESP8266 uses deep-sleep mode to conserve power, and (hopefully) for long battery life. 
I’m temporarily using a cheap small breadboard and occasionally, for some reason, the discrete DS18B20 loses connectivity 🙁 , so I got a couple of Protoboards to put this simple circuit on permanently. I still need to figure out a better weatherproof enclosure; right now, I’m using a couple plastic food containers, one as a rain cover, which works OK for now. I was getting ridiculous temperature readings from the discrete on-board DS1820 – like 100 degrees F, and I’m sure it’s because the late winter morning sun hits the enclosure. I have lowered the platform the temperature monitor rests on, so the sun doesn’t hit it. It’s working pretty well now; I’m checking the temperatures every 2 hours. Doing so every hour made the chart a little busy. Now to make another one for my little “greenhouse”.