Advisories

000
WTPZ42 KNHC 272050
TCDEP2
 
Hurricane Polo Discussion Number  29
NWS National Hurricane Center Miami FL       EP172026
200 PM MST Sun Sep 27 2026
 
A NOAA P-3 Hurricane Hunter aircraft was able to complete two fixes 
into Polo earlier this afternoon, indicating the hurricane was more 
or less steady state. In the final fix, the aircraft reported a   
22 n mi closed eyewall, though in the wind data there was some 
evidence of a double wind maximum at 700 mb even though the 
secondary wind max was not seen in the Tail Doppler Radar wind 
data. The peak flight-level winds were 117 kt, which typically 
reduces to 105 kt using a standard 0.9 reduction. However, the 
aircraft did not fully sample the eastern quadrant where higher 
winds may exist. In addition, subjective and objective satellite 
intensity estimates remain at or above 110 kt, so Polo's initial 
intensity will be held at 110 kt this advisory.

Polo is continuing its turn, now moving northward at 355 degrees at 
10 kt. The synoptic setup and track reasoning has not chanced much 
this cycle, with Polo expected to move between deep-layer ridging 
centered over Mexico and a shortwave trough that will soon move into 
California. This trough is forecast to sweep southward, helping to 
capture the smaller Polo, leading it to accelerating to the 
northeast. The NHC track forecast this cycle is largely an update of 
the previous one this morning, though there remains more along-track 
spread, related to Polo's speed of motion, than across-track spread. 
This latest track lies closest to the Google DeepMind ensemble mean 
(GDMI). With the latest update to the track, a Hurricane Warning 
has now been issued for portions of mainland Mexico along the Gulf 
of California. 

Vertical wind shear in the SHIPS guidance is in the 5-10 kt range 
for the next 12-24 h while the hurricane traverses 28-29 C 
sea-surface temperatures, so Polo's short-term intensity will likely 
be controlled by inner-core fluctuations. Given the double wind 
maxima that appeared in the earlier aircraft data, it is not out of 
the question another eyewall replacement cycle (ERC) could occur 
before Polo makes landfall along the west Baja California Sur 
coastline. The latest NHC intensity forecast shows very little 
change in strength before Polo reaches the coast, and the latest 
forecast now anticipates Polo making landfall at near major 
hurricane intensity. In fact, both the 12z HAFS-A/B raw model output 
show Polo making landfall as a major hurricane even if their 
interpolated aids are a bit lower in intensity. Significant 
weakening should occur as it moves over the rugged terrain of the 
Baja California Peninsula, but Polo will likely still be a hurricane 
when it makes its second landfall in mainland Mexico. Rapid 
weakening is forecast thereafter and Polo will likely dissipate 
before the middle of this week over the Mexican Plateau. 
 
Polo is expected to dissipate before it reaches the southern U.S., 
but distant moisture associated with it and Odalys will be 
transported into the southwestern United States during the next few 
days, 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 
Warning is in effect for that region. Tropical storm conditions 
could reach portions of the coast as soon as tonight or early 
Monday, making further preparations difficult. These conditions will 
likely spread across Baja California through Monday and into 
mainland Mexico on early Tuesday. A storm surge is likely, 
especially in areas of onshore winds.
 
2. Heavy rainfall associated with Polo may begin to impact Baja 
California Sur later tonight into Tuesday and portions of Sonora 
late Monday into Tuesday. This rainfall may produce life-threatening 
flooding and mudslides, especially in areas of steep terrain.  
Moisture from Polo will support heavy rainfall and flooding 
potential across the Southwest U.S. into the Southern High Plains 
late Monday into Tuesday.
 
3. Dangerous surf and rip currents are likely along portions of
the northwest coast of Mexico and Baja California for the next
few days.
 
 
FORECAST POSITIONS AND MAX WINDS
 
INIT  27/2100Z 21.9N 114.1W  110 KT 125 MPH
 12H  28/0600Z 23.2N 114.0W  110 KT 125 MPH
 24H  28/1800Z 25.0N 113.0W  105 KT 120 MPH
 36H  29/0600Z 27.0N 111.3W   75 KT  85 MPH...OVER WATER
 48H  29/1800Z 29.9N 108.7W   35 KT  40 MPH...INLAND
 60H  30/0600Z...DISSIPATED
 
$$
Forecaster Papin