Hurricane Polo

000
WTPZ42 KNHC 260853
TCDEP2
 
Hurricane Polo Discussion Number  23
NWS National Hurricane Center Miami FL       EP172026
200 AM MST Sat Sep 26 2026

The NOAA aircraft that flew in Polo from 25/22Z to 26/01Z found 
maximum flight-level winds of 154 kt, corresponding to about 140 kt 
surface winds using standard reduction factors.  Since that time, 
the structure of Polo has continued to look very impressive on 
satellite imagery.  The eye has become a bit more cloud-filled 
with cooling infrared eye temperatures only over the last hour or 
two.  The latest intensity estimate from TAFB is 7.5/155 kt and 
latest objective estimates from UW-CIMSS range from 133-153 kt.  
The ADT estimate of 167 kt looks a bit unrealistically too high, 
given some of the other observed data.  Based on the earlier recon 
data and the recent cooling observed in the eye, the intensity is 
nudged downward slightly to 145 kt.

Polo is expected to remain in a favorable environment for another 
48 hours although sea-surface temperatures and ocean heat content 
will begin decreasing after hour 24.  As Polo approaches Baja 
California Sur, increasing southwesterly wind shear is expected to 
cause a faster rate of weakening.  The NHC intensity forecast is 
near the high end of the model guidance suite through 48 hours.  
Thereafter, the NHC forecast lies between the middle and high end 
of the guidance.  Polo is expected to be a powerful hurricane when 
it reaches Baja California Sur, and it likely to still be a 
hurricane when it reaches mainland northwestern Mexico.

The initial motion estimate is west-northwestward, or 290 degrees at 
8 kt. There is no change to the track forecast reasoning with this 
advisory. The hurricane is expected to turn gradually northwestward 
tomorrow, then northward by the end of the weekend while it moves 
around the western side of a ridge centered over northern Mexico. 
Early next week an upper-level trough approaching from the northwest 
will cause the hurricane to turn northeastward toward Baja 
California Sur and west-central Mexico. The NHC track forecast is 
very similar to the previous advisory, and is slightly slower than 
the latest HCCA and GDMI, but much faster than the latest TVCN 
consensus.  The track guidance is good agreement in that there is 
very little cross-track spread.  However, there are still some 
timing differences (quite a bit of along-track spread).  With this 
in mind, residents in Baja California Sur and northwestern Mexico 
should consider finishing their preparations by Sunday.
 
Distant moisture from Hurricane Polo and Odalys will be transported
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. Polo is forecast to approach the west coast of the Baja
California peninsula on Monday as a hurricane, and a Hurricane
Watch is in effect for that region. Tropical Storm conditions
could reach portions of the coast as soon as late Sunday, making 
further preparations difficult. A storm surge will be possible, 
especially in areas of onshore winds.
 
2. Heavy rainfall associated with Polo may begin to impact Baja 
California Sur late Sunday into Monday. This rainfall may produce 
life-threatening flooding and mudslides, especially in areas of 
steep terrain.
 
3. Dangerous surf and rip currents are likely along portions of
the northwest coast of Mexico and Baja California for the next 
several days.
 
 
FORECAST POSITIONS AND MAX WINDS
 
INIT  26/0900Z 17.6N 111.0W  145 KT 165 MPH
 12H  26/1800Z 18.3N 112.1W  145 KT 165 MPH
 24H  27/0600Z 19.7N 113.3W  135 KT 155 MPH
 36H  27/1800Z 21.5N 113.8W  125 KT 145 MPH
 48H  28/0600Z 23.4N 113.8W  110 KT 125 MPH
 60H  28/1800Z 25.1N 113.2W   95 KT 110 MPH
 72H  29/0600Z 26.9N 111.6W   75 KT  85 MPH
 96H  30/0600Z 30.3N 107.5W   30 KT  35 MPH...INLAND
120H  01/0600Z...DISSIPATED
 
$$
Forecaster Hagen