Polo, advisory 5

000
WTPZ32 KNHC 212050
TCPEP2
 
BULLETIN
Hurricane Polo Advisory Number   5
NWS National Hurricane Center Miami FL       EP172026
300 PM CST Mon Sep 21 2026
 
...NOAA HURRICANE HUNTER AIRCRAFT SHOWS POLO RAPIDLY INTENSIFYING...
 
 
SUMMARY OF 300 PM CST...2100 UTC...INFORMATION
----------------------------------------------
LOCATION...15.1N 102.7W
ABOUT 290 MI...465 KM SSE OF MANZANILLO MEXICO
ABOUT 195 MI...310 KM SSW OF ZIHUATANEJO MEXICO
MAXIMUM SUSTAINED WINDS...85 MPH...140 KM/H
PRESENT MOVEMENT...ESE OR 110 DEGREES AT 6 MPH...9 KM/H
MINIMUM CENTRAL PRESSURE...974 MB...28.77 INCHES
 
 
WATCHES AND WARNINGS
--------------------
CHANGES WITH THIS ADVISORY:
 
None.
 
SUMMARY OF WATCHES AND WARNINGS IN EFFECT:
 
A Tropical Storm Watch is in effect for...
* Tecpan de Galeana to Punta San Telmo
 
A Tropical Storm Watch means that tropical storm conditions are
possible within the watch area, generally within 48 hours.
 
The Tropical Storm Watch will likely be expanded westward later
today or tonight.
 
For storm information specific to your area, please monitor
products issued by your national meteorological service.
 
 
DISCUSSION AND OUTLOOK
----------------------
At 300 PM CST (2100 UTC), the center of Hurricane Polo was located 
by a NOAA Hurricane Hunter aircraft near latitude 15.1 North, 
longitude 102.7 West. Polo is moving toward the east-southeast near 
6 mph (9 km/h).  This general motion is expected tonight, with a 
sharp turn towards the northwest and west-northwest anticipated 
late Tuesday into Wednesday.  On the forecast track, the core is 
Polo is expected to be near or south of the coast of southwestern 
Mexico during the next few days.
 
Maximum sustained winds have increased to near 85 mph (140 km/h) 
with higher gusts.  Polo is expected to continue rapidly 
intensifying, becoming a major hurricane by Tuesday, with further 
intensification likely though midweek.
 
Hurricane-force winds extend outward up to 25 miles (35 km) from the
center and tropical-storm-force winds extend outward up to 70 miles
(110 km).
 
The estimated minimum central pressure is 974 mb (28.77 inches).
 
 
HAZARDS AFFECTING LAND
----------------------
Key messages for Polo can be found in the Tropical Cyclone
Discussion under AWIPS header MIATCDEP2 and WMO header WTPZ42 KNHC.
 
WIND: Tropical storm conditions are possible within the watch
area by Tuesday night or early Wednesday.
 
RAINFALL: Polo is expected to produce rainfall totals of 4 to 8 
inches, with isolated maximum totals up to 12 inches across coastal 
portions of the Mexican states of Guerrero and Michoacn through 
Thursday. This rainfall may produce life-threatening flooding and 
mudslides, especially in areas of steep terrain. Rainfall of 3 to 6 
inches is possible in coastal portions of Oaxaca, Colima, and 
Jalisco through Thursday.
 
For a complete depiction of forecast rainfall associated with Polo,
please see the National Weather Service Storm Total Rainfall
Graphic available at
hurricanes.gov/graphics_ep2.shtml?rainqpf
 
SURF:  Swells generated by Polo are expected to begin affecting
portions of the coast of southwestern Mexico on Tuesday. These
swells are likely to cause life-threatening surf and rip current
conditions.  Please consult products from your local weather office.
 
 
NEXT ADVISORY
-------------
Next intermediate advisory at 600 PM CST.
Next complete advisory at 900 PM CST.
 
$$
Forecaster Blake
 

000
WTPZ42 KNHC 212052
TCDEP2
 
Hurricane Polo Discussion Number   5
NWS National Hurricane Center Miami FL       EP172026
300 PM CST Mon Sep 21 2026
 
Satellite images show that Polo has a ragged eye on both visible
and infrared images, with very deep convection starting to wrap
around a broken eyewall.  The NOAA Hurricane Hunter aircraft has
been providing valuable data that show the cyclone undergoing an
early-stage eyewall cycle, with two wind maxes on the TDR radar.
The plane recently reported 0.5 km winds up to 92 kt, with
higher winds and lower central pressure on each fix, dropping about 
1 mb per hour.  These winds convert to roughly 75 kt at the 
surface, and that will be the initial wind speed this advisory.
 
While the current eyewall replacement could slightly hinder 
intensification, the last aircraft pass through Polo already showed 
that the old inner eyewall was fading.  Thus, given the very warm 
waters, light shear and moist environment, a high-end rapid 
intensification event is expected.  The latest model guidance are 
even higher than the last cycle, and the new NHC intensity forecast 
follows the trend, but is still below the NOAA HCCA corrected- 
consensus aid.  An increase in easterly wind shear could cause some 
weakening in the medium-range period, though Polo should be a small 
and powerful hurricane throughout the forecast period.
 
The storm is drifting east-southeastward and should move in that 
general direction for about a day before a mid-level ridge 
intensifies over Mexico.  This ridge should cause the cyclone to 
turn sharply towards the northwest and west-northwest on Wednesday 
and Thursday, bringing the core of the storm near or south of the 
coast of southwestern Mexico.  Eventually there is enough troughing 
over the eastern Pacific to cause the system to bend more 
northwestward at long range towards the Baja California peninsula.  
The details, however, are pretty sketchy with a potential binary 
interaction with Tropical Storm Odalys looming, which is helping to 
cause a large north-south spread in the guidance.  No big changes 
were made to the NHC forecast, but it is a little farther west at 
and beyond 72 hours where uncertainty is high.  
 
 
Key Messages:
 
1. Heavy rainfall associated with Polo will impact coastal portions 
of southwest Mexico through Thursday. This rainfall may produce 
life-threatening flooding and mudslides, especially in areas of 
steep terrain.
 
2. Polo is forecast to strengthen to a major hurricane while it
moves closer to the coast of southwestern Mexico during the next few
days. Although the core of the hurricane is forecast to stay
offshore, it is too soon to determine the exact location or
magnitude of impacts. Residents in southwestern Mexico should
closely monitor its progress and updates to the forecast. A Tropical
Storm Watch is in effect for portions of southwestern Mexico.
 
 
FORECAST POSITIONS AND MAX WINDS
 
INIT  21/2100Z 15.1N 102.7W   75 KT  85 MPH
 12H  22/0600Z 14.9N 102.3W  100 KT 115 MPH
 24H  22/1800Z 14.9N 102.0W  125 KT 145 MPH
 36H  23/0600Z 15.4N 102.2W  140 KT 160 MPH
 48H  23/1800Z 16.1N 102.9W  145 KT 165 MPH
 60H  24/0600Z 17.0N 104.0W  140 KT 160 MPH
 72H  24/1800Z 17.7N 105.5W  140 KT 160 MPH
 96H  25/1800Z 18.6N 108.6W  130 KT 150 MPH
120H  26/1800Z 20.5N 111.2W  120 KT 140 MPH
 
$$
Forecaster Blake