Pacific Hurricane Feed

Tropical Storm Howard Forecast Discussion



000
WTPZ44 KNHC 080837
TCDEP4

Tropical Storm Howard Discussion Number   8
NWS National Hurricane Center Miami FL       EP092022
300 AM MDT Mon Aug 08 2022

Howard appears to be continuing its strengthening trend.  A 
scatterometer pass at 0507 UTC revealed surface wind speeds peaking 
around 40 kts in the northern semicircle of the circulation.  The 
satellite data also revealed the tropical storm to be quite a bit 
smaller than originally estimated.  Subjective Dvorak estimates from 
TAFB and SAB both support an intensity of 45 kt.  Given the 
potential for the scatterometer to under sample winds in a smaller 
storm, the initial intensity has been increased to matched the 
Dvorak estimates.

The window for additional potential strengthening is growing 
shorter.  SHIPS model guidance indicates Howard should move over 
the 26 degree Celsius sea surface isotherm in about 24 hours.  The 
global models forecast the vertical wind shear to increase and the 
surrounding environmental relative humidities to decrease.  The 
combination of these oceanic and atmospheric conditions should 
induce a weakening trend.  The official forecast predicts 
Howard to plateau in intensity at 50 kt and become post-tropical 
by 60 hours.

The reasoning behind the track forecast is unchanged.  The tropical 
storm is moving northwestward at 12 kt on the southwest periphery 
of a mid-level ridge.  When Howard weakens, the cyclone is expected 
to turn westward in the low-level tradewind flow.  The updated 
track forecast is very similar to the previous prediction and 
remains close to the model consensus aids.


FORECAST POSITIONS AND MAX WINDS

INIT  08/0900Z 19.2N 112.6W   45 KT  50 MPH
 12H  08/1800Z 20.4N 113.9W   50 KT  60 MPH
 24H  09/0600Z 21.7N 115.5W   50 KT  60 MPH
 36H  09/1800Z 22.8N 117.3W   50 KT  60 MPH
 48H  10/0600Z 23.6N 119.1W   45 KT  50 MPH
 60H  10/1800Z 24.3N 120.8W   35 KT  40 MPH...POST-TROPICAL
 72H  11/0600Z 24.6N 122.5W   30 KT  35 MPH...POST-TROP/REMNT LOW
 96H  12/0600Z 24.6N 125.4W   30 KT  35 MPH...POST-TROP/REMNT LOW
120H  13/0600Z 24.0N 128.0W   25 KT  30 MPH...POST-TROP/REMNT LOW

$$
Forecaster Bucci/Brown



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