I would not go the CC3000 route - even though it was the only real option at the time I was connecting Espruino to wifi. ESP8266 is for sure the prevailing option today... Since you have only a simple task of measuring the temp and transmit the data, you may even stay ESP8266 'native'/LUA. On the other hand, ESPRUINO's JS is available on ESP8266 as well, you can stick with JS. How you finally move forward depends on your expecations and how much you want to invest - not just in € | $, but also in number of 'moving' parts and 'variety' of parts: 'involving' MQTT, the cloud, various platforms...
Espruino is a JavaScript interpreter for low-power Microcontrollers. This site is both a support community for Espruino and a place to share what you are working on.
I would not go the CC3000 route - even though it was the only real option at the time I was connecting Espruino to wifi. ESP8266 is for sure the prevailing option today... Since you have only a simple task of measuring the temp and transmit the data, you may even stay ESP8266 'native'/LUA. On the other hand, ESPRUINO's JS is available on ESP8266 as well, you can stick with JS. How you finally move forward depends on your expecations and how much you want to invest - not just in € | $, but also in number of 'moving' parts and 'variety' of parts: 'involving' MQTT, the cloud, various platforms...