Tropical Depression Five-E Forecast Discussion

662 
WTPZ45 KNHC 041435
TCDEP5

Tropical Depression Five-E Discussion Number   1
NWS National Hurricane Center Miami FL       EP052024
800 AM MST Sun Aug 04 2024

Convection associated with a low located well offshore Mexico has 
steadily increased in coverage and organization since yesterday. 
Overnight ASCAT and first-light visible imagery indicate that the 
cyclone also has a well-defined, if somewhat broad, circulation. 
Subjective Dvorak classifications from TAFB and SAB were both 2.0 
at 1200 UTC, which support initiating advisories on the system as a 
30 kt depression.

The depression is located within a very convectively active 
environment over the east Pacific, deep-layer wind shear is low, and 
SSTs are plenty warm, so strengthening is expected in the short 
term. The biggest source of uncertainty for this forecast is an 
expected interaction with a larger disturbance, currently Invest 
96E, which is approaching from the east. Based on the available 
global and hurricane dynamical model forecasts, the most likely 
scenario is that 96E will be the dominant system. In that case, the 
new depression will only have a short window to strengthen before it 
is wrapped into and dissipates within the other circulation. Models 
historically handle interaction cases like this poorly, so 
confidence in the forecast is not high, despite the near universal 
agreement between the dynamical guidance on this upcoming evolution.

The NHC forecast is very close to the consensus guidance through 24 
to 36 h.  After that, the model trackers appear to be getting fooled 
by the close proximity of 96E and TD Five-E and are following the 
stronger vortex instead. The NHC forecast is based heavily on a 
broad consensus of model fields beyond 36 h and shows dissipation 
occuring by 60 h.  There is some chance that the depression could 
persist longer than forecast if the two systems remain farther 
apart, however there is not enough guidance with a trackable vortex 
to justify an explicit forecast beyond what is currently shown.


FORECAST POSITIONS AND MAX WINDS

INIT  04/1500Z 15.8N 112.9W   30 KT  35 MPH
 12H  05/0000Z 15.4N 113.0W   35 KT  40 MPH
 24H  05/1200Z 14.5N 113.4W   40 KT  45 MPH
 36H  06/0000Z 13.8N 113.4W   45 KT  50 MPH
 48H  06/1200Z 14.1N 112.8W   45 KT  50 MPH
 60H  07/0000Z...DISSIPATED

$$
Forecaster D. Zelinsky