Atlantic/2019/05L/Archive/26

Once again, the bout of intensification of the previous day has ended. Dorian's appearance has been pretty steady on infrared satellite imagery since the previous advisory. Some signs of dry air affecting the hurricane, particularly the collapse of the cloud deck in the northwest quadrant and the outflow feature emanating from this area, are present. This is likely a result of the wind shear mentioned last advisory which is causing the convection's asymmetry. The initial intensity remains 120 kt this advisory.
Given the signs of shear and dry air, combined with the shrinkage of the eye, becoming somewhat evident in the latest satellite frames, and the perfect banding setup, Dorian is poised for an eyewall replacement cycle. It is fairly likely that one will begin later today and that this will continue to prevent intensification and perhaps induce a bit of weakening. Model analyses actually indicate that wind shear is likely to remain present at current levels for the next 36 hours or so before increasing slightly. This may be able to prevent Dorian from experiencing any significant strengthening beyond its current intensity. What Dorian does have going for it is that after today ample oceanic heat content and some increase in mid-level moisture will provide a more supportive environment for an even stronger storm, so if Dorian is going to reach the upper end of category 4 strength or stronger, it would most likely happen sometime on day 2. Beyond this, some upwelling is possible as the hurricane slows down significantly beginning on day 3, inducing weakening. Later still, increasing shear and decreasing mid-level moisture will further this weakening trend.
Dorian continues to move west-northwest this morning south of a building ridge located over the southeastern US. The hurricane should continue to track more westerly as a result of the ridge's strengthening over the next two days, with some slowing occurring beginning late on day 2 as an approaching upper-level trough weakens the ridge. This will allow Dorian to track toward the northwest into the weakness, likely staying offshore of Florida until a second trough passes to the hurricane's north, pulling it more northward and eventually recurving it northeastward on day 5 as it approaches the Carolinas. The dynamical guidance has shifted further offshore of Florida with the 00z suite of models, likely as a result of a better initialization of the mid-level cyclone currently located over Missouri. The existence of this feature was under-forecast by models until late yesterday and it has allowed for the lowering of heights where the mid-level ridge was expected to be, which is expected to have the effect of passing troughs having a stronger eroding effect on the ridging, which will allow Dorian to track slower and turn toward the north. It is becoming increasingly likely that Dorian will be more of a threat to states further up the eastern seaboard, in particular the Carolinas than it will be to the state of Florida, although it is still possible that the hurricane will scrape the Floridian coast with resulting effects despite not making landfall there. On the other hand, this change in track does not affect the Bahamas that much, with Dorian expected to pass over or just north of the islands of Great Abaco and Grand Bahama as a category 4 hurricane late on day 2 into day 3.
FORECAST MAX WINDS
INIT 31/0900Z 120 KT 140 MPH
12H 31/1800Z 115 KT 130 MPH
24H 01/0600Z 120 KT 140 MPH
36H 01/1800Z 125 KT 145 MPH
48H 02/0600Z 130 KT 150 MPH
72H 03/0600Z 125 KT 145 MPH
96H 04/0600Z 110 KT 125 MPH