Since there is some controversy, I want to clear some issues. I definitely trust the TPC, and DrewFL makes a valid point - people's excitement and interest over a system can (understandably) overrule rational judgement. I do think this site is an excellent source of information - I have learned an immense amount of information and outstanding tips from the talented interesting people (professional, amateur, and all backgrounds) on these forums. I think you should ignore posts if they disrupt your thoughts or decisions. Most people probably do not intend to deliberately offer frivolous information. We can learn from everyone on this site.
I was going conservative in my original post (tomorrow night is my earliest estimate) - I simply believe (based on data and my personal observations) that 90L may develop sooner than some people think (albeit not as quick a pace that is indicated by some models). I do agree - convective activity is limited in aerial coverage, and this factor leads many early season easterly waves into a "death knell" when they encounter a stable air mass or shear. This system is different - the SAL has retreated northward; the 500 mbar Azores ridge is weaker; and we are gradually entering a regime that is more conducive for development. Personally, I think this wave has sustained a persistent convective "burst" close to the sfc low for more than 24 hours. This trend could indicate more rapid development, especially because of the lower easterly shear ahead of the system.
Here are some good links:
Saharan Air Layer analysisOceanic heat contentThis system has maintained convection and structural organization within a hostile mid-level environment (i.e. stratocumulus and SAL). Additionally, the SAL layer has weakened, and the system is entering warmer heat content (i.e. more unstable air mass). This factor could aid convective sustenance, and the well-defined sfc low depicted by QuikSCAT seems to offer some support for this hypothesis. Obviously, these waves typically develop slowly, and I don't support the idea of extremely rapid consolidation and cyclogenesis. I do think there are some positive signs for development - current trends indicate the possibility it could occur within 36 to 48 hours. I think this wave has passed the "critical point" for its survival.
By the way, I enjoy your posts!