Each tool on Fishtrack has its advantages and limitations. We need to use a combination of these tools to identify changes in the sea state, in order to find fish. The more tools utilized, the higher chance of locking into a hotspot. Once you understand the data sources' limitations you will be able to understand when & how to use them properly.
"Latest SST" imagery is the most accurate sea temperature tool. When possible, use the latest imagery first, as it will be the most recent data available. But you may find that the Latest SST images are mostly blank, due to cloud cover...
Cloudfree SST combines multiple recent SST images to "fill in the blanks". This is a great tool to "build an image" when clouds are problematic, but the temperature data may not be as recent/accurate as with the raw satellite images.
If recent SST images have been mostly blank, it is safe to assume that the Cloudfree SST product may not be the most accurate of the available tools to utilize in order to find "breaks".
You might prefer to utilize a slightly older, but raw SST image vs the Cloudfree product. As long as your area of interest hasn't been blocked by clouds, the improved resolution of the raw image will make identifying breaks easier.
The Sea Surface Height overlay isn't affected by cloud cover and provides us with clues about water temperature. In areas of upwelling, the SSH will be below mean sea level. In areas of downwelling, the SSH will likely be above mean sea level. Upwellings can be identified by areas that are lower than surrounding areas. It's a bit counter-intuitive, but basically, water in these "low spots" is rising to the surface in an effort to achieve equilibrium.
SSH data overlays won't line up precisely with satellite imagery, but you will see that the data sources correspond and can be used when there is no recent satellite imagery to go off of. It's certainly better than driving around blind, particularly when you are aware of the limitations of the data.
The altimetry-derived currents overlay shows how currents flow around highs (clockwise) in the Northern Hemisphere.