MySpool Temperature Alert (WP) comes with a high-quality waterproof temperature sensor which can be used to measure both air and liquid temperatures.

It can operate in two modes. One mode sends alerts when temperature goes above or below your thresholds. And the second mode allows you to send data to a ThingSpeak channel for display and analysis. See here for directions on how to setup this free data channel.

It sends alerts when temperature goes above or below your thresholds. And it can show a chart of the last 24 hours as well as send data to a ThingSpeak channel for display and analysis. For more details and to order one see here.