Issued at 300 AM GMT Mon Aug 30 2021 


380 
WTNT41 KNHC 300246
TCDAT1
 
Post-Tropical Cyclone Julian Discussion Number   5
NWS National Hurricane Center Miami FL       AL112021
300 AM GMT Mon Aug 30 2021
 
Julian has been showing signs of a transition into an extratropical 
cyclone over the past several hours. The deep convection has become 
detached to the northeast from the low-level center and cloud tops 
of that convection are warming. A line of convection to the south of 
the center resembles a frontal boundary, with recent scatterometer 
data showing a notable wind shift along that line. Based on the 
structural changes noted above, as well as a majority of FSU 
phase-space diagrams from the various global models, Julian is 
estimated to have transitioned to an extratropical cyclone. Recent 
ASCAT data showed the cyclone's intensity remains 50 kt. The cyclone 
is forecast to maintain this intensity through Monday before 
weakening. It is then forecast to dissipate in a few days over the 
northern Atlantic. The system should continue to move quickly 
northeastward through Monday, then turn northward and northwestward 
Monday night into Tuesday. 
 
This is the last advisory on Julian by the National Hurricane 
Center. Additional information on this system can be found in High 
Seas Forecasts issued by the National Weather Service, under AWIPS 
header NFDHSFAT1, WMO header FZNT01 KWBC, and online at 
ocean.weather.gov/shtml/NFDHSFAT1.php 
 
 
FORECAST POSITIONS AND MAX WINDS
 
INIT  30/0300Z 38.1N  41.9W   50 KT  60 MPH...POST-TROPICAL
 12H  30/1200Z 40.3N  39.0W   50 KT  60 MPH...POST-TROP/EXTRATROP
 24H  31/0000Z 44.1N  36.4W   50 KT  60 MPH...POST-TROP/EXTRATROP
 36H  31/1200Z 48.5N  36.2W   45 KT  50 MPH...POST-TROP/EXTRATROP
 48H  01/0000Z 53.0N  38.2W   40 KT  45 MPH...POST-TROP/EXTRATROP
 60H  01/1200Z 57.0N  40.0W   40 KT  45 MPH...POST-TROP/EXTRATROP
 72H  02/0000Z...DISSIPATED
 
$$
Forecaster Latto



Source: Post-Tropical Cyclone Julian Forecast Discussion Number 5