Eastern Pacific Basin Tropical Cyclones

Tropical Storm Madeline Forecast Discussion


000
WTPZ44 KNHC 190857
TCDEP4

Tropical Storm Madeline Discussion Number   7
NWS National Hurricane Center Miami FL       EP142022
300 AM MDT Mon Sep 19 2022

Madeline continues to produce an healthy area of deep convection, 
though this activity continues to be somewhat displaced to the 
southwest of the center due to moderate northeasterly shear. We 
finally received some long awaited scatterometer data at 0357 UTC, 
which had a peak wind retrieval of 48-kt in the southern semicircle 
of Madeline's circulation. Satellite estimates were also somewhat 
higher, with TAFB at T3.5/55-kt, SAB at T3.0/45-kt, and ADT at 
T3.2/49-kt. A combination of these intensity estimates support 
raising the intensity to 50 kt for this advisory.

Fixes from both scatterometer and microwave data indicate that 
Madeline is continuing its northwest heading, estimated at 320/8 kt. 
As mid-level ridging builds in to the north, the storm is expected 
to turn toward the west-northwest later today and gradually bend 
more westward through the end of its lifespan as a tropical cyclone. 
While a lot of the guidance continues to be tightly clustered, there 
remain a few outliers that are further to the north (HWRF/ 
Experimental HAFS-S). The latest track forecast was nudged a bit 
further north, mostly related to the initial position and motion, 
but after 24 hours is very close to the previous forecast track, but 
just a touch faster, in agreement with the TVCE and HCCA consensus 
aids.

While I cannot rule out that Madeline might intensify a bit more in 
the next 6-12 h, the easterly vertical wind shear that has been 
plaguing the storm is forecast to increase further later today, as 
the storm moves over rapidly cooling sea-surface temperatures, 
crossing the 26 C isotherm in about 24 hours. Thus, weakening is 
expected to begin by tonight, and simulated satellite imagery 
suggests organized deep convection will cease in 36-48 hours, with 
the latest forecast still showing Madeline becoming a remnant low by 
that time. The latest NHC intensity forecast is in good agreement 
with the intensity consensus aids. 


FORECAST POSITIONS AND MAX WINDS

INIT  19/0900Z 20.3N 108.2W   50 KT  60 MPH
 12H  19/1800Z 20.9N 109.4W   50 KT  60 MPH
 24H  20/0600Z 21.4N 110.8W   45 KT  50 MPH
 36H  20/1800Z 21.7N 112.1W   35 KT  40 MPH
 48H  21/0600Z 21.9N 113.4W   30 KT  35 MPH...POST-TROP/REMNT LOW
 60H  21/1800Z 22.0N 114.7W   25 KT  30 MPH...POST-TROP/REMNT LOW
 72H  22/0600Z 21.9N 116.1W   25 KT  30 MPH...POST-TROP/REMNT LOW
 96H  23/0600Z 21.7N 118.8W   20 KT  25 MPH...POST-TROP/REMNT LOW
120H  24/0600Z 21.5N 122.0W   20 KT  25 MPH...POST-TROP/REMNT LOW

$$
Forecaster Papin



Source link