I have been using the Temperature Stick all year in my coach and it has worked great. We use it to monitor temps when we leave the dog in the coach but I also use it when I have it parked for extreme temps and humidity. It runs on two AA batteries so it can be used without AC power and it gets great battery life. I use rechargeable batteries and I haven't charged them in a couple months.
It will send text and / or email alerts for high or low temps and high or low humidity levels. You can configure alerts just about any way you like.
It is a bit pricey but it has been rock solid. You can usually get it cheaper on their website vs Amazon. They just had a $20 off sale for Labor Day.
https://www.amazon.com/Wireless-Temp...xpY2s9dHJ1ZQ==
https://tempstick.com/?gclid=Cj0KCQj...caAijOEALw_wcB