Atlantic Basin Tropical Cyclones

Tropical Storm Karl Forecast Discussion


000
WTNT44 KNHC 122055
TCDAT4

Tropical Storm Karl Discussion Number   6
NWS National Hurricane Center Miami FL       AL142022
400 PM CDT Wed Oct 12 2022

The overall satellite presentation of Karl has improved since early 
this morning, but the system is being affected by moderate 
westerly shear.  The center is located near the western edge of a 
persistent cluster of convection that has cloud top temperatures of 
around -80C. As mentioned in the earlier Special Advisory, an Air 
Force Reserve reconnaissance aircraft measured a peak 850-mb 
flight level wind of 58 kt and SFMR winds of around 50 kt as it 
exited the eastern portion of the storm.  There has been little 
overall change in structure since the plane departed, so the initial 
intensity is held at 50 kt.  Another reconnaissance mission into the 
storm is scheduled for this evening. 

Karl has continued to move northward, but its poleward progress 
is forecast to end very soon.  A ridge building over northern 
Mexico is forecast to start steering the cyclone generally 
southward later tonight or early Thursday.  A southward motion 
should then continue, and this motion is expected to bring 
the center near the southern coast of Bay of Campeche on Friday. 
The 1200 UTC dynamical model guidance suite is in slightly better 
agreement, but it was once again east of the previous NHC advisory. 
Another fairly significant eastward shift was required, but the 
latest forecast is now closer to the consensus aids as well as 
a blend of the GFS and ECMWF models. 

Karl is located over warm water but within an area of moderate 
westerly wind shear.  The shear is forecast to increase slightly, 
however some additional slight strengthening is possible in the 
short term.  After that, the shear and slightly lower mid-level 
humidity is expected to cause gradual weakening before Karl reaches 
the coast of Mexico.  After landfall, rapid weakening and 
dissipation should occur.  The NHC wind speed forecast is slightly 
higher than before, and it is not much different than the latest 
ICON and HCCA consensus aids. 


Key Messages:

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

2. Tropical storm conditions are possible in the watch area in
Mexico beginning on Friday.


FORECAST POSITIONS AND MAX WINDS

INIT  12/2100Z 22.2N  94.4W   50 KT  60 MPH
 12H  13/0600Z 22.2N  94.3W   55 KT  65 MPH
 24H  13/1800Z 21.4N  94.0W   50 KT  60 MPH
 36H  14/0600Z 20.5N  93.8W   50 KT  60 MPH
 48H  14/1800Z 19.5N  93.8W   45 KT  50 MPH
 60H  15/0600Z 18.7N  94.0W   40 KT  45 MPH
 72H  15/1800Z 17.5N  94.7W   25 KT  30 MPH...POST-TROP/REMNT LOW
 96H  16/1800Z...DISSIPATED

$$
Forecaster Brown



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