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Its now pretty clear what is going on. #HurricaneKarl #TSKarl is caught in an atmospheric river generated by #TD99E (in a similar way to how #HurricaneIan was) and headed towards florida - not Mexico.
The second overlay is a special "steering" product that allows you to see where a cyclone is headed - it focusses on the 500-850hpa wind range (1.5 to 5.5kms high winds ) which are particularly important for pushing cyclones. 
And as you can see #HurricaneKarl is being steered towards northern Florida at present.
This IR satelllite image [src: @TropicalTidbits] shows #TSKarl is unquestionably now #HurricaneKarl. It also shows it is not moving towards the Mexico coast line as per the current @NHC_Atlantic forecast - but moving NE. And the transformation into this was 3 hours ago.
Here are its first three hours as a hurricane.
