Pacific Hurricane Feed

Tropical Storm Howard Forecast Discussion



663 
WTPZ44 KNHC 072036
TCDEP4

Tropical Storm Howard Discussion Number   6
NWS National Hurricane Center Miami FL       EP092022
300 PM MDT Sun Aug 07 2022

Since this morning, convection has been attempting to build over the 
northern semicircle of the cyclone. While the low-level circulation 
remains partially exposed to the south, the coldest cloud tops below 
-70 C have rotated cyclonically in the up-shear direction, which 
could foreshadow an attempt of the mid-level center aligning with 
the low-level center in the future. Subjective and objective Dvorak 
intensity estimates this afternoon were a consensus T2.5/35 kt. 
Consequently, Tropical Depression Nine-E has been upgraded to 
Tropical Storm Howard with 35 kt winds this advisory.

The storm has continued a general motion to the northwest, estimated
at 315/10 kt. The track philosophy has not changed much today, as
Howard should continue to move northwestward into a relative
weakness in the mid-level ridging. The track guidance this cycle has
taken a noticeable shift to the northwest over the first 24-48 hours
of the forecast, and the latest NHC track has also been shifted in
that direction. Thereafter, Howard is likely to become vertically
shallow, and increasingly steered by the low-level flow. The track
forecast after 48 hours shows a bend westward in response to
this transition, and follows closely with the consensus aids HCCA 
and TVCE.

The short-term intensity forecast is interesting. While Howard is 
clearly still feeling some effects of southwesterly vertical wind 
shear, the deepest convection has pivoted into the northern side of 
the storm. This could be the first signs that the upper-level trough 
to the west of Howard is starting to weaken and shift away from the 
storm. In addition, the raw model output grids of the GFS, ECMWF, 
and HWRF all suggest some sort of center reformation or relocation 
under the convection between 12-36 hours. This process may help to 
align the low and mid-level centers of the storm. This improved 
structure would also likely result in more intensification than 
previously shown, and the latest intensity forecast now takes Howard 
up to 50 kt in 36 hours. After that, the storm will be crossing a 
sharp sea surface temperature gradient and moving into a more stable 
environment, ultimately leading to steady weakening and its demise 
as a tropical cyclone by 96 hours. The latest NHC intensity forecast 
has a higher peak than before, but is still a tad under the latest 
HCCA guidance.


FORECAST POSITIONS AND MAX WINDS

INIT  07/2100Z 17.6N 110.7W   35 KT  40 MPH
 12H  08/0600Z 19.0N 111.8W   40 KT  45 MPH
 24H  08/1800Z 20.6N 113.3W   45 KT  50 MPH
 36H  09/0600Z 21.8N 115.0W   50 KT  60 MPH
 48H  09/1800Z 22.9N 116.8W   50 KT  60 MPH
 60H  10/0600Z 23.8N 118.5W   40 KT  45 MPH
 72H  10/1800Z 24.5N 120.1W   35 KT  40 MPH
 96H  11/1800Z 25.0N 123.0W   30 KT  35 MPH...POST-TROP/REMNT LOW
120H  12/1800Z 24.5N 126.0W   25 KT  30 MPH...POST-TROP/REMNT LOW

$$
Forecaster Papin




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