Daily Satellite Sea Surface Temperature Anomaly
The NOAA Coral Reef Watch (CRW) daily 5-km Sea Surface Temperature (SST) Anomaly product displays the difference between today's SST and the long-term average. The scale goes from -5 to +5 °C. Positive numbers mean the temperature is warmer than average; negative means cooler than average.
See here for CRW's twice-weekly 50 km products, updated around 2 pm on Mondays and Thursdays.