First up on the discussion is Hurricane Danielle.
The center appears to be on the eastern side of the convection as essentially all the convection is on the western side. This is pretty much a one sided hurricane as the system has been having trouble getting the convection to wrap around the center.
Yesterday evening the eye was developing and then unexpectedly dry air intrusion started working its way into the center, Danielle had taken on a ragged appearance. This morning she had a defined eye but once again it seems as though the eye could be starting to cover itself back up.
Presently Danielle is maintaining herself and as of 18 Z the pressure is 970 mbs and still a 90 KT hurricane. Danielle has had a existence where she seems to perk up in the evening and then in the overnight she starts to become more lackluster in appearance. This system has been fighting against light to at times moderate shear and dry air as well.
As of 18 Z the shear and dry air looks like this ..
So the present shear is actually 20-30 knots with the anti cyclone a little to the SW of where Danielle actually is. Shear does not seem to be decreasing as was what was expected by the National Hurricane Discussion in there forecast discussion from 5 AM
Instead it is actually shown as increasing to the north of Danielle.
So is Danielle a threat to the east coast? The answer to this is no. Danielle was never a threat to the east coast with the exception of some models like the NOGAPS and occasionally a few runs of the GFS. The ECM has never showed this system as being a threat to the East Coast. The system should continue to work its way Northwest around a mid level ridge before being picked up by a trough coming off the east coast which will then cause the system to turn more north and then northeast away from the east coast.
Intensity wise…Danielle has gone thru weakening phases and strengthening phases and essentially every time she starts to try and strengthen some dry air works its way back into the system and prevents it from happening.
So i think any development yet is going to continue to be slow to occur and will continue the same general pattern of persistence with this system. If Danielle can shake off the shear and dry air then she could very well become a Major Hurricane but the combination of the shear and dry air might be just enough of a hinderance to keep this from really kick starting.
Next on the discussion plate of systems is Tropical Storm Earl.
Despite Earl being labeled as a Tropical Storm you can see from the two images above that Earl is having some difficulties. I think these difficulties arise from a combination of shear and dry air as the image below shows.
And from this perspective Earl looks like a tropical system that is under these conditions as the convection has been warming over the past several hours. Latest image as of 18:45 UTC is below:
So until these conditions improve i expect any development to be slow to occur with this system.
Next up is an invest PGI36 . Out of all the tropical systems at hand this one actually has the best environment as far as shear is concerned . Shear is only around 5-10 knots around the system but more shear to the west around 20 knots. However the best convergence and divergence currently lies to the west of the system. However..this system is also pretty much surrounded by dry air.
So there is alot of action going on in the tropics at the present point and time. Hurricane Danielle and Tropical Storm Earl. None of these systems at this point and time are a threat to the east coast. Danielle certainly is not a threat and for now at least it appears as Earl will end up following the same path as what Danielle did. So at this point and time there is really no point in issuing any type of track guidance. If anything should change with either storm then a conus track would be issued…
As far as the potential Fiona models are suggesting that Fiona will develop in the long range. I will cover that once the system develops and moves up into the shorter range.
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