Advisories

000
WTPZ42 KNHC 270857
TCDEP2
 
Hurricane Polo Discussion Number  27
NWS National Hurricane Center Miami FL       EP172026
200 AM MST Sun Sep 27 2026
 
The satellite presentation of Polo has remained fairly steady since
the time the NOAA aircraft finished its mission about 7 hours ago.
There are still hints of an eye in geostationary and microwave
satellite images. The latest TAFB Dvorak currently intensity was
6.5/127 kt with 5.5/102 kt for the final-T number.  Objective
intensity estimates from UW-CIMSS have been running in the 105-110
kt range.  The initial intensity is held at 105 kt for this
advisory.
 
Polo has turned toward the north-northwest, with the current motion 
estimated at 330/9 kt.  A turn toward the north is expected later 
today, and then northeastward on Monday as the cyclone continues to 
move around the ridge and becomes increasingly affected by a mid- to 
upper-level trough moving in from the northwest. The largest source 
of uncertainty in the forecast continues to be the forward speed of 
Polo as it makes its expected northeastward turn between the 
aforementioned synoptic features. The model spread remains higher 
than unusual between 48 and 72 h, more so for the along-track 
forward speed of the storm after landfall. The NHC forecast follows 
the path of the GDMI and HCCA, but is a bit slower than those 
models.  This forecast is essentially on top of the previous NHC 
forecast.
 
Polo will continue to travel through an environment of fairly weak 
vertical wind shear and sea-surface temperatures near 29C for the 
next 24 h, but will be moving into a somewhat drier airmass.  By 
hour 36, which is about 6 hours before landfall, southwesterly 
vertical wind shear will increase.  Due to the favorable conditions 
until almost before the Baja California landfall, the NHC forecast 
is near the higher end of the guidance suite through hour 36, 
showing only gradual weakening.  Thereafter, increasing wind shear 
and land interaction will cause rapid weakening.  Although waters 
are warm in the Gulf of California, Polo is not expected to 
restrengthen there due to strong southwesterly vertical wind shear. 
 The intensity forecast for the 2nd landfall (in mainland Mexico) 
is tricky.  There is some possibility that Polo could still be at
hurricane strength for the 2nd landfall, as suggested by the latest 
HAFS-A forecast.  Polo should dissipate inland over northern Mexico 
by hour 72.
 
Polo is expected to become a remnant low and then dissipate before
it reaches the southern U.S., but distant moisture associated with
it and Odalys will be transported into the southwestern United
States late 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
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. A storm
surge is likely, especially in areas of onshore winds.
 
2. Heavy rainfall associated with Polo may begin to impact Baja 
California Sur tonight into Tuesday. 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
few days.
 
 
FORECAST POSITIONS AND MAX WINDS
 
INIT  27/0900Z 20.3N 113.6W  105 KT 120 MPH
 12H  27/1800Z 21.6N 114.0W  100 KT 115 MPH
 24H  28/0600Z 23.4N 114.0W   95 KT 110 MPH
 36H  28/1800Z 25.1N 113.1W   90 KT 105 MPH
 48H  29/0600Z 26.8N 111.6W   70 KT  80 MPH
 60H  29/1800Z 28.9N 109.3W   40 KT  45 MPH
 72H  30/0600Z 31.3N 106.8W   25 KT  30 MPH...POST-TROP/INLAND
 96H  01/0600Z...DISSIPATED
 
$$
Forecaster Hagen