It isn't looking too impressive at the moment, but then as you said it probably has something to do with the diurnal rise and fall. It might look a little better in the morning.

The TWD has something interesting to say about a wave in the C. Atlantic:-

NUMERICAL GUIDANCE INDICATES THE
UPPER LEVEL PATTERN MAY BECOME A BIT MORE FAVORABLE DURING THE
NEXT DAY OR SO AS AN UPPER RIDGE DEVELOPS TO THE NE AND A
TROUGH FORMS OVER THE E CARIBBEAN. THIS MAY RESULT IN SOME
INCREASE IN SHOWER/THUNDERSTORM ACTIVITY AS THE WAVE NEARS THE
LESSER ANTILLES.

Could be interesting in a few days. There are warm SSTs, the SAL is not too potent in that region, but there is a pall of dry air hanging throughout most of the Caribbean. Still, maybe this wave will be something to watch in a few days.

BTW, doesn't Dr Gray release his updated forecast next week? It will be interesting to see whether he leaves his numbers the same or not.