Hurricane Polo

000
WTPZ42 KNHC 250248
TCDEP2
 
Hurricane Polo Discussion Number  18
NWS National Hurricane Center Miami FL       EP172026
800 PM MST Thu Sep 24 2026

Powerful Polo continues to have an impressive presentation on 
satellite imagery.  The eye is estimated to be around 20 n mi in 
diameter and is embedded within a 180 n mi wide Central Dense 
Overcast of very cold cloud tops.  The upper-level outflow 
pattern is quite symmetrical, indicative of weak vertical wind shear 
over the system.  The advisory intensity is held at 130 kt, in 
reasonable agreement with a subjective Dvorak estimate from TAFB and 
objective estimates from UW-CIMSS.

The hurricane is now moving on a mainly westward track with an 
initial motion estimated to be about 280/9 kt.  There is little 
change to the track forecast philosophy from the previous advisory. 
Polo is currently being steered by the flow on the south 
side of a well-defined mid-tropospheric ridge that is building 
westward over northern Mexico.  This steering regime should 
continue through Friday.  After that, a mid-latitude trough moving 
eastward across the northeastern Pacific should prevent the ridge 
from building farther west, with Polo likely to recurve northward 
and northeastward around the western periphery of the ridge.  The 
track guidance is generally in agreement on this scenario, although 
there are still notable differences in forward speed among the 
models in the 3-5 day time frame.  The official forecast is similar 
to the previous one, aside from showing a bit wider turn around the 
ridge before nearing the Baja California Peninsula in around 96 
hours.  This is a blend of the latest GDMI and HCCA solutions.

Polo will continue to move over very warm waters and in a low 
vertical wind shear environment through Friday.  Given the conducive 
conditions, the hurricane could regain category 5 intensity soon.  
Around 36 hours, a gradual weakening trend is expected to begin due 
to some increase in shear.  The official intensity forecast is on 
the high side of the model guidance, and shows the system still 
near major hurricane strength while it approaches the Baja 
California peninsula.  Rapid weakening is expected when the cyclone 
crosses the peninsula and moves into mainland Mexico.
 
It should be noted that moisture from Hurricane Polo and Odalys
will be carried a long distance into the southwestern United States
this weekend and early next week, and may indirectly contribute to
a heavy rainfall and flash flood threat in the region. See products
issued by the Weather Prediction Center for more information.
 
 
Key Messages:

1. Heavy rainfall associated with Polo will impact coastal portions 
of southwest Mexico through the evening.  This rainfall may produce 
life-threatening flooding and mudslides, especially in areas of 
steep terrain.
 
2. Wind gusts to tropical storm force may still occur along 
portions of the southwestern coast of Mexico this evening.
 
3. Polo is forecast to approach the Baja California Peninsula early
next week as a hurricane.  Interests there should closely monitor
the latest updates and ensure that they have their preparedness
plan in place.
 
 
FORECAST POSITIONS AND MAX WINDS
 
INIT  25/0300Z 17.1N 106.5W  130 KT 150 MPH
 12H  25/1200Z 17.4N 108.1W  140 KT 160 MPH
 24H  26/0000Z 17.5N 110.0W  130 KT 150 MPH
 36H  26/1200Z 18.0N 111.6W  120 KT 140 MPH
 48H  27/0000Z 19.2N 112.9W  115 KT 130 MPH
 60H  27/1200Z 20.8N 113.7W  110 KT 125 MPH
 72H  28/0000Z 22.6N 114.0W  105 KT 120 MPH
 96H  29/0000Z 25.7N 112.5W   95 KT 110 MPH
120H  30/0000Z 27.3N 109.8W   60 KT  70 MPH...INLAND
 
$$
Forecaster Pasch