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Post-Tropical Cyclone Nine-E Forecast Discussion


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000
WTPZ44 KNHC 010838
TCDEP4

Post-Tropical Cyclone Nine-E Discussion Number   7
NWS National Hurricane Center Miami FL       EP092021
1100 PM HST Sat Jul 31 2021

The depression has remained poorly organized for more than 24 hours 
and has produced a very limited amount of convection during that 
time. As a result of the lack of organized deep convection over the 
past day, the system no longer meets the definition of a tropical 
cyclone, and it has degenerated into a remnant low.  In addition, 
the original low-level swirl that was tracked over the past day or 
so appears to have been absorbed within the envelope of the broader
low pressure area.  The system's initial intensity is maintained 
at 25 kt, but this could be generous. 

The depression has been plagued by shear and dry air entrainment, 
and those conditions are expected to persist for at least the next 
couple of days.  If the system is able to survive past 72 hours, 
there is some chance of redevelopment when the shear decreases 
later in the period.  However, given the uncertainty surrounding 
the potential interaction with Hurricane Hilda located to the 
cyclone's northeast, the official forecast calls for the system to 
remain a remnant low, and this will be the final NHC advisory on 
this system unless regeneration occurs.

The cyclone has been nearly stationary overnight, but it is 
forecast to begin a slow westward to west-northwestward motion later 
today, and that motion should continue for the next few days. 
After that time, possible interaction with Hilda increases the track 
forecast uncertainty, but since the majority of the dynamical 
models keep the low on a west-northwestward heading, so does the 
NHC forecast. 

Future information on the remnant low can be found in High Seas 
Forecasts issued by the National Weather Service, under AWIPS header 
NFDHSFEPI, WMO header FZPN02 KWBC, and on the web at 
ocean.weather.gov/shtml/NFDHSFEPI.php  

Information on potential regeneration will be available in the 
Tropical Weather Outlook as needed. 


FORECAST POSITIONS AND MAX WINDS

INIT  01/0900Z 11.4N 127.5W   25 KT  30 MPH...POST-TROP/REMNT LOW
 12H  01/1800Z 11.8N 128.3W   25 KT  30 MPH...POST-TROP/REMNT LOW
 24H  02/0600Z 12.0N 129.9W   25 KT  30 MPH...POST-TROP/REMNT LOW
 36H  02/1800Z 12.3N 131.5W   25 KT  30 MPH...POST-TROP/REMNT LOW
 48H  03/0600Z 12.7N 132.9W   25 KT  30 MPH...POST-TROP/REMNT LOW
 60H  03/1800Z 13.1N 134.2W   25 KT  30 MPH...POST-TROP/REMNT LOW
 72H  04/0600Z 13.5N 135.5W   25 KT  30 MPH...POST-TROP/REMNT LOW
 96H  05/0600Z 14.5N 137.8W   25 KT  30 MPH...POST-TROP/REMNT LOW
120H  06/0600Z 15.5N 140.5W   25 KT  30 MPH...POST-TROP/REMNT LOW

$$
Forecaster Brown