Tropical Storm Fabio Discussion Number 7
Wiki-Hurricanes Forecast Center
4:00 PM CDT Sun Jul 1 2018
Fabio is undergoing a structural change this afternoon. The robust central dense overcast seen last night has given way to less central convection, with deep bands of convection beginning to form around the circulation in what will likely become a banded eye scene type in a few hours. Water vapor imagery and maps from the GFS indicate Fabio is being lightly sheared from a displaced anticyclone to its east. Nonetheless, satellite intensity estimates range from T3.0/45kt from SAB, to 53kt from SATCON, to T3.5/55kt from TAFB and UW-CIMSS ADT. A blend of these estimates supports a perhaps conservative initial intensity of 50kt.
No change to the track forecast to discuss. Fabio is moving west-northwest, steered by expansive mid-level ridging across Mexico. This motion is expected to continue unimpeded for the next 5 days.
The shear Fabio is experiencing is expected to decrease tonight, setting the stage for a period of explosive intensification over warm water temperatures and amid an abundantly moisture environment. The GFS has trended increasingly bullish with the system since yesterday, with the latest 12z run now indicating a minimum pressure of 908mb—well within the threshold of Category 5 strength. The SHIPS has also past that threshold, indicating peak winds of 146kt. It should be noted, however, that both models show this peak while Fabio is over water temperatures near 27°C; this is about a degree cooler than one would expect for a Category 5 hurricane. The LGEM has increased to 133kt, whereas the HWRF remains one of the more bearish models with a strong Category 3 cyclone. While I am not quite ready to increase the forecast as high as most of these models indicate, it is clear that some upward adjustment is needed, especially with the SHIPS now indicating a 8-in-10 chance of 25kt rapid intensification over the next day. Weakening should begin after 48 hours as Fabio enters a drier environment over cooler waters.
FORECAST POSITIONS AND MAX WINDS
INIT 01/2100Z 50 KT 60 MPH
12H 02/0600Z 65 KT 75 MPH
24H 02/1800Z 85 KT 100 MPH
36H 03/0600Z 120 KT 140 MPH
48H 03/1800Z 125 KT 145 MPH
72H 04/1800Z 115 KT 130 MPH
96H 05/1800Z 75 KT 85 MPH
120H 06/1800Z 40 KT 45 MPH
