If in fact either or both of these African waves pan out, kudos to the GFS model for having sniffed them out for some time now. Variances exist with regards to timing, however several other models have more recently jumped on board with regard to eventual development. For the most part, the GFS model has been pretty consistent with these systems re-curving, however I am a little reluctant to be so quick to accept this as a given. Accuracy of long distance forecasting not withstanding, I am puzzled by the persistent tendency for the GFS model to continue to forecast such motion, where corresponding 500mb flow would seem to indicate 594 heights in some cases just north and northwest of a supposed system. Even assuming that any organized low does congeal farther north around 15N, GFS models show an earlier NW motion than what the heights and orientation of the mid level ridging would seem to justify.
Only reason I even bother to mention this, is that it is one thing to speculate on the potential accuracy of any particular model, providing even having a tropical cyclone in place. I'm not so sure I am willing to give to much credence to suspect forecast motion on a system that has yet to develop ( or determining where it will actually develop ). Point is I do believe subtle changes are occurring with regards to the upper air, both over the Conus and likely over the Atlantic. So, may it be climatology, La Nina, or that huge chunk of ice recently calved off from Greenland ( perhaps not ), I think it bears stating that despite any "instant re-curve projections" on the part of any particular model, no one should take anything for granted; at least not until some consensus of short term models with a system in place would seem to indicate overwhelming evidence.
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