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