000
WTPA44 PHFO 062055
TCDCP4
 
Tropical Storm Pena Discussion Number   1
NWS Central Pacific Hurricane Center Honolulu HI   CP042026
Issued by NWS National Hurricane Center Miami FL
1100 AM HST Fri Nov 06 2026

Satellite imagery indicates that an area of low pressure (Invest 
CP95) that we have been monitoring for several days has developed a 
well-defined circulation, showing banded convection around its 
center. While the most recent constrained subject Dvorak analysis 
from HFO was CI number was 2.0/30 kt, the Data T was 3.0/45 kt, 
which probably better reflects the system's organization. A 1546 UTC 
SMOS microwave pass supports that assessment, showing winds above 
tropical-storm-force east of the center. Based on this, advisories 
have been initiated on Tropical Storm Pena, with an intensity of 40 
kt.

The initial motion is estimated to be westward, or 280/10 kt, and 
the storm is expected to continue this motion for the next several 
days due to a high pressure ridge centered over the Central Pacific. 
Model guidance remains in good agreement through 72 h on Pena's 
track, then cross-track spread increases among the model solutions, 
resulting in lower-than-normal confidence. Additionally, the storm's 
initial representation in much of the guidance is too weak, which 
adds another layer of uncertainty. The NHC track forecast has been 
set to follow the GDMI and HCCA aids.

The intensity forecast is tricky because the overall environment 
generally seems conducive to strengthening for at least the next day 
or so. While there is an increase in shear in much of the models 
this weekend, this shear could abate early next week, with no 
obvious dry air or instability issues seen in the large-scale 
guidance. It is a little puzzling why many of the models show little 
change or even a weakening so quickly in seemingly conducive 
conditions, though perhaps it is linked to the unrealistically weak 
initial vortex representation of Pena.  The first forecast is on the 
higher side of the guidance and reflects a blend of some aids that 
get close to hurricane-strength, while others weaken to a 
depression. It probably goes without saying that this too is an 
uncertain prediction, similar to the track forecast.
 
 
FORECAST POSITIONS AND MAX WINDS
 
INIT  06/2100Z 11.3N 150.1W   40 KT  45 MPH
 12H  07/0600Z 11.5N 151.8W   45 KT  50 MPH
 24H  07/1800Z 11.4N 153.9W   50 KT  60 MPH
 36H  08/0600Z 11.3N 155.8W   50 KT  60 MPH
 48H  08/1800Z 11.3N 157.8W   50 KT  60 MPH
 60H  09/0600Z 11.2N 159.7W   50 KT  60 MPH
 72H  09/1800Z 11.0N 161.8W   50 KT  60 MPH
 96H  10/1800Z 11.3N 165.9W   50 KT  60 MPH
120H  11/1800Z 11.9N 171.4W   50 KT  60 MPH
 
$$
Forecaster Pierce/Blake