EPAC: WILLA - Remnants

[northjaxpro]

Looks like Willa is well in the process of becoming a major hurricane in the next 36 hours or sooner. She is impressive already, with about as ideal upper level environmental conditions you will find with a cyclone. Overall, very good outflow and impressive deep convective tops beginning to fire up and spiraling within the inner core.

[Yellow Evan]

Hello everyone, I'm an American living in Puerto Vallarta, I've lurked on this forum a long time marveling at the beauty of tropical cyclones worldwide, yet looking at the forecast path, and how it keeps nudging more south, I'm getting Kenna vibes from this. I was here in 2002, and although there wasn't horrific damage, there was rampant looting everywhere, power outages for about a week, and with it having to survive in horrible 90F days with dewpoints in the 75F range sans AC.

Needless to say, it is not an experience I would like to go through again, do any of you have any thoughts as of now?

I'm only worried if the storm passes slightly north of us, since due to the angle of the bay and the high mountains surrounding it, storms making landfall to the South bring nothing more than a few showers, such as was experienced during hurricane Patricia 3 years ago. If I am to expect conditions similar to or worse than with Kenna, I will definitely board up my house (more to prevent looting than anything else) and make a drive to Guadalajara with a hotel reservation for a few days.

Kenna was located closer to the coast and likely had less time to weaken. Furthermore, both the GFs and ECMWF currently in Nayrait where you'd most likely avoid the inner core.

[Yellow Evan]

Can already tell this is going to make a run at Cat 5.

[WAcyclone]

New F-17 pass from 35 minutes ago shows a partial eyewall structure on the western side:

[cycloneye]

SUMMARY OF 900 AM MDT...1500 UTC...INFORMATION
----------------------------------------------
LOCATION...16.6N 106.7W
ABOUT 270 MI...435 KM SSW OF CABO CORRIENTES MEXICO
MAXIMUM SUSTAINED WINDS...100 MPH...155 KM/H
PRESENT MOVEMENT...NW OR 325 DEGREES AT 7 MPH...11 KM/H
MINIMUM CENTRAL PRESSURE...975 MB...28.80 INCHES


WATCHES AND WARNINGS
--------------------
CHANGES WITH THIS ADVISORY:

The government of Mexico has issued a Hurricane Watch for the coast
of Mexico from San Blas northward to Mazatlan, and a Tropical Storm
Watch from Playa Perula northward to south of San Blas.


Hurricane Willa Discussion Number 6
NWS National Hurricane Center Miami FL EP242018
900 AM MDT Sun Oct 21 2018

First-light GOES-16 visible satellite imagery shows that Willa
continues to become better organized, with a tightly coiled band
of convection wrapping around the center. There has also been
evidence of a small eye in recent microwave and infrared satellite
pictures. Subjective and objective satellite intensity estimates
range from 77 kt to 90 kt, and the initial intensity has been
increased to 85 kt for this advisory.

Willa is moving northwestward or 325/6 kt. The track guidance
continues to indicate that Willa will move northwestward today,
then turn northward on Monday, and then head north-northeastward
on Tuesday between a deep-layer ridge that extends westward from the
Gulf of Mexico and an approaching mid-level trough. The dynamical
model guidance remains in good overall agreement on this scenario,
but there are differences in how quickly Willa will accelerate
north-northeastward. The UKMET and ECMWF are much slower than the
remainder of the dynamical models, with the GFS and GFS ensemble
mean the fastest. The NHC track forecast brings the center of the
Willa onshore of the coast of southwestern Mexico within 72 h, and
it lies closest to the HFIP corrected consensus, which is a little
faster than the other consensus aids.

The hurricane is expected to remain within low vertical wind shear
and over warm waters of around 28 degrees Celsius during the next
day or two. These very favorable conditions are expected to allow
steady to rapid strengthening through Monday night, and the NHC
forecast is near the upper end of the intensity guidance. By 48
hours, increasing southwesterly shear is forecast to initiate
weakening, but Willa is likely to remain a very strong hurricane
through landfall in southwestern Mexico. After landfall, rapid
weakening and dissipation over the mountainous terrain of mainland
Mexico should occur.

Key Messages:

1. Willa is forecast to be a hurricane when it reaches the coast of
southwestern mainland Mexico by late Tuesday or Wednesday bringing a
life-threatening storm surge, dangerous winds, and life-threatening
flash flooding, and hurricane and tropical storm watches are now
in effect for a portion of the area. Residents in the watch areas
should monitor the progress of this system and follow any advice
given by local officials.


FORECAST POSITIONS AND MAX WINDS

INIT 21/1500Z 16.6N 106.7W 85 KT 100 MPH
12H 22/0000Z 17.2N 107.2W 95 KT 110 MPH
24H 22/1200Z 18.2N 107.6W 110 KT 125 MPH
36H 23/0000Z 19.3N 107.7W 120 KT 140 MPH
48H 23/1200Z 20.4N 107.5W 110 KT 125 MPH
72H 24/1200Z 23.3N 105.5W 80 KT 90 MPH...INLAND
96H 25/1200Z 26.5N 101.0W 20 KT 25 MPH...POST-TROP/INLAND
120H 26/1200Z...DISSIPATED

$$
Forecaster Brown

[Yellow Evan]

New F-17 pass from 35 minutes ago shows a partial eyewall structure on the western side:

[url]https://i.imgur.com/MTr0Jdr.jpg

To be honest, I expected more than that at this point.

[WAcyclone]

New F-17 pass from 35 minutes ago shows a partial eyewall structure on the western side:

[url]https://i.imgur.com/MTr0Jdr.jpg

To be honest, I expected more than that at this point.

Willa looks, however, very impressive on visual/IR imagery and I also think it's quite likely there's a closed 37 GHz cyan ring which would help with rapid eyewall formation. Unfortunately, the 37 GHz band doesn't have a very high resolution on the SSMIS instrument:

[Highteeld]

[StruThiO]

[cycloneye]

BULLETIN
Hurricane Willa Intermediate Advisory Number 6A
NWS National Hurricane Center Miami FL EP242018
1200 PM MDT Sun Oct 21 2018

...WILLA CONTINUES TO STRENGTHEN...
...HURRICANE AND TROPICAL STORM WATCHES IN EFFECT FOR PARTS OF THE
SOUTHWESTERN COAST OF MEXICO...


SUMMARY OF 1200 PM MDT...1800 UTC...INFORMATION
-----------------------------------------------
LOCATION...16.8N 106.9W
ABOUT 260 MI...420 KM SSW OF CABO CORRIENTES MEXICO
MAXIMUM SUSTAINED WINDS...105 MPH...165 KM/H
PRESENT MOVEMENT...NW OR 325 DEGREES AT 7 MPH...11 KM/H
MINIMUM CENTRAL PRESSURE...971 MB...28.67 INCHES


WATCHES AND WARNINGS
--------------------
CHANGES WITH THIS ADVISORY:

None

SUMMARY OF WATCHES AND WARNINGS IN EFFECT:

A Hurricane Watch is in effect for...
* San Blas to Mazatlan

A Tropical Storm Watch is in effect for...
* Playa Perula to San Blas

[Yellow Evan]

----- Current Analysis -----
Date : 21 OCT 2018 Time : 171536 UTC
Lat : 16:43:11 N Lon : 106:53:23 W


CI# /Pressure/ Vmax
4.6 / 974.0mb/ 79.6kt


Final T# Adj T# Raw T#
4.6 5.0 6.0

Estimated radius of max. wind based on IR : 8 km

Center Temp : -10.0C Cloud Region Temp : -67.0C

Scene Type : EYE

[Highteeld]

Looks like 95-100 knot range.

[cycloneye]

Is good to know that Recon will fly on Monday.

[Yellow Evan]

TXPZ24 KNES 211823
TCSENP

A. 24E (WILLA)

B. 21/1800Z

C. 16.8N

D. 106.8W

E. ONE/GOES-W

F. T5.5/5.5/D2.0/24HRS

G. IR/EIR/VIS

H. REMARKS...SYSTEM CHARACTERIZED BY AN OW EYE SURROUNDED BY B AND
EMBEDDED IN LG FOR DT=5.5 AFTER ADDING .5 FOR AN EYE ADJUSTMENT. MET
AND PT ARE 5.0. FT IS BASED ON DT.

I. ADDL POSITIONS

NIL


...FISHER

[supercane4867]

I think Willa has a decent chance to shoot for the third CAT5 of the season.

[Yellow Evan]

This is going places.

[Kingarabian]

https://i.imgur.com/fkZVSsG.jpg

This is going places.

Yup, looks like all systems go for cat.4 status. Cyan rings rarely disappoint.

[Yellow Evan]

Yea this is a major or at least close to it.

[Ntxw]

It's good recon coming in tomorrow. Very tight core now and deep, cold convection. Might be candidate for cat 5

[Yellow Evan]

----- Current Analysis -----
Date : 21 OCT 2018 Time : 184536 UTC
Lat : 16:49:11 N Lon : 106:58:12 W


CI# /Pressure/ Vmax
5.2 / 963.5mb/ 94.8kt


Final T# Adj T# Raw T#
5.2 6.0 6.1

Estimated radius of max. wind based on IR : 9 km

Center Temp : -11.2C Cloud Region Temp : -69.1C

Scene Type : EYE