It is not much bigger than New Jersey. Over the last several years, NHC has been increasingly naming everything in sight. This particular example goes a long way toward showing this trend. Water vapor imagery shows the original disturbance rotating around the back(west) side of a large mid/upper trough stalled out over the Azores:
It was named a tropical storm at 3Z and at 41.2 N lat, 20.3 W lon over 70 degree F (21 C) waters.
Over such cool waters, deep convection can only be supported by the steep lapse rate environment provided by the mid-level trough.
A moist adiabat from 21 C at sea level will only reach around -8 C at 500 mb. If that parcel were placed in the tropics, where 500 mb temps are seen to be about -5 C, this would be likley produce a positive lifted index.
Another non-tropical feature is the horizontal thermal contrast - although given Grace's small size it might be argued that the storm itself doesn't even cross more than one isotherm.
In addition, the best low-level moisture is displaced well to the southeast of the low pressure center - just like almost any typical mid-latitude system.
This is especially obvious at 850:
Even with systems like this being named, tropical activity in the Atlantic should be below normal this year.
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