Atlantic Basin Tropical Cyclones

Tropical Storm Karl Forecast Discussion


982 
WTNT44 KNHC 130835
TCDAT4

Tropical Storm Karl Discussion Number   8
NWS National Hurricane Center Miami FL       AL142022
400 AM CDT Thu Oct 13 2022

Karl has become less organized since the last advisory due to the 
effects of increasing northwesterly vertical wind shear.  The 
central convection has decreased, and the strongest convection is 
now occurring in a band well east of the center.  Surface wind 
estimates received from an Air Force Reserve Hurricane Hunter 
aircraft since the last advisory were in the 40-45 kt range, and 
recently-received scatterometer data showed no winds higher than 40 
kt.  In addition, the last aircraft-reported central pressure had 
risen to 1002 mb.  Based on these data, the initial intensity is 
reduced to 45 kt.

Karl remains nearly stationary.  A mid-level ridge located over 
west-central Mexico and a high-amplitude mid-latitude trough over 
the eastern United States are expected to impart northerly or 
northwesterly flow over Karl today, which should push the cyclone 
southeastward and southward into the Bay of Campeche during the 
next couple of days.  A turn toward the southwest could occur near 
the end of the forecast period as the steering flow becomes more 
northeasterly.  The guidance has changed little since the previous 
advisory, and the new forecast track has only minor adjustments 
from the previous forecast.  The new track shows the center of Karl 
reaching the Mexican coast in Tabasco or Veracruz states by Saturday 
morning.

A combination of northwesterly vertical wind shear and dry air 
entrainment should cause Karl to gradually weaken during the next 
couple of days, and the new intensity forecast shows a little more 
weakening before the cyclone makes landfall.  This part of the 
intensity forecast lies near the upper edge of the intensity 
guidance.  After landfall, quick weakening is expected, with Karl 
forecast to become a depression by 60 h, a remnant low by 72 h, and 
dissipate by 96 h.  The new intensity forecast has some minor 
adjustments from the previous forecast due to the reduced initial 
intensity.


Key Messages:

1. Heavy rainfall associated with Karl could produce instances of 
flash flooding, with mudslides in areas of higher terrain, across 
portions of Veracruz, Tabasco, Chiapas and Oaxaca states in Mexico.

2. Tropical storm conditions are possible in the watch area in
Mexico beginning late Friday or early Saturday.


FORECAST POSITIONS AND MAX WINDS

INIT  13/0900Z 22.4N  94.4W   45 KT  50 MPH
 12H  13/1800Z 21.7N  93.9W   45 KT  50 MPH
 24H  14/0600Z 20.7N  93.6W   45 KT  50 MPH
 36H  14/1800Z 19.7N  93.5W   40 KT  45 MPH
 48H  15/0600Z 18.7N  93.9W   40 KT  45 MPH
 60H  15/1800Z 17.4N  94.6W   30 KT  35 MPH...INLAND
 72H  16/0600Z 16.4N  95.4W   20 KT  25 MPH...POST-TROP/REMNT LOW
 96H  17/0600Z...DISSIPATED

$$
Forecaster Beven




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