CPAC: LANE - Post-Tropical

[WAcyclone]

Current radar:



This loop can be found at http://wx.graphics/models/MRMS_radar_hawaii.gif

[PandaCitrus]

so what exactly is going to happen with the big blob of rain north of the center? Without a core anymore, the only thing important is the rain. How much rain will fall, where, and what will the flooding be like?

[Mauistorms]

My question as well!

[Nimbus]

Forecast still has it moving off to the west after 48 hours which is much better than what happened with Harvey. The up slope rain problems the mountains present is similar to Haiti with a lot of habitats near watershed rivers and streams that can expand 10 fold in volume near the base of the mountains. That in turn can flood out power substations and make a real mess. Have to pay attention to the local EM guidance that knows the issues for your area.

[wxman57]

Recent microwave shots indicate that Lane has decoupled or is decoupling. LLC is way down near 18.3N / 158.1W-158.2W. I wouldn't think that it would qualify for an upgrade to hurricane strength given that its LLC is now separated from the convection. Still heavy rain for the islands, but no hurricane-force winds.

[cycloneye]

BULLETIN
Hurricane Lane Advisory Number 41
NWS Central Pacific Hurricane Center Honolulu HI EP142018
1100 AM HST Fri Aug 24 2018

...SLOW-MOVING LANE CONTINUING TO BRING FLOODING RAINFALL AND STRONG
GUSTY WINDS TO PARTS OF HAWAII...


SUMMARY OF 1100 AM HST...2100 UTC...INFORMATION
-----------------------------------------------
LOCATION...19.1N 157.9W
ABOUT 150 MI...245 KM S OF HONOLULU HAWAII
ABOUT 130 MI...205 KM WSW OF KAILUA-KONA HAWAII
MAXIMUM SUSTAINED WINDS...105 MPH...165 KM/H
PRESENT MOVEMENT...N OR 360 DEGREES AT 5 MPH...7 KM/H
MINIMUM CENTRAL PRESSURE...966 MB...28.53 INCHES


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

The Hurricane Watch for Kauai has been changed to a Tropical Storm
Watch for Kauai and Niihau.

[OahuWahine]

It seems like Lane slows by 1 mph at every update. Is there a chance of it stalling as it gets closer to Maui and Oahu?

[BYG Jacob]

He ain't dead yet.

[Shell Mound]

Actually, the fact that Lane is decoupling quickly means the actual rainfall totals over the Hawaiian Islands will likely be significantly less than the "doomsday" GFS estimates. The weakening of the circulation means that orographic effects are going to be less significant than originally feared. Additionally, the shear vectors indicate that the strongest divergence (and hence convection and precipitation rates) is on the northwestern side of the circulation, which means that, as a weaker system is likely to stay farther offshore, the threat of significant rainfall over the islands is likely to be more limited/localised and less extreme than feared. This is good news overall for Hawaii. I think the 50"+ estimates are going to be far too high and that the actual totals will be 20-25" at most in a few spots.

[BobHarlem]

He ain't dead yet.

The CCC is gone, it'll probably go downhill (intensity wise) quickly from here.

[Shell Mound]

Recent microwave shots indicate that Lane has decoupled or is decoupling. LLC is way down near 18.3N / 158.1W-158.2W. I wouldn't think that it would qualify for an upgrade to hurricane strength given that its LLC is now separated from the convection. Still heavy rain for the islands, but no hurricane-force winds.

http://wxman57.com/images/Lane2.JPG

As an aside, does anyone know why there hasn't been any reconnaissance mission since 22 August? Considering the threat to land, logically there should have been.

[Kingarabian]

It seems like Lane slows by 1 mph at every update. Is there a chance of it stalling as it gets closer to Maui and Oahu?

The threat of this being a slow mover has been there for a while. How slow it's going to he and how long it'll take for Lane to leave the area remains to be seen.

[wxman57]

As an aside, does anyone know why there hasn't been any reconnaissance mission since 22 August? Considering the threat to land, logically there should have been.

Recon had to evacuate the island (Oahu) due to the hurricane threat. There's nowhere else they can fly from and reach Lane.

[wxman57]

Here's a visible image with surface obs plotted. If someone just showed me this graphic and asked my opinion (knowing nothing of Lane's past) I'd be hard-pressed to say it has an LLC, much less a Dvorak of 5.0 and 90 kt winds.

[NDG]

There's no way Lane still is a hurricane, why is the CPHC so slow to upgrade or downgrade the systems?

[floridasun78]

There's no way Lane still is a hurricane, why is the CPHC so slow to upgrade or downgrade the systems?

look tropical wave

[ava_ati]

There's no way Lane still is a hurricane, why is the CPHC so slow to upgrade or downgrade the systems?

Because it is a 6 hour flight from the mainland, one way, and if they don't have planes stationed nearby they can't fly missions into it. I think they all err on the side of caution when basing forecasts purely on satellite & radar. Better to have a minimal storm with people expecting a cat 2 than to have a cat 2 and everyone expecting a depression.

[wxman57]

New satellite, exposed center, convection dissipating - torn apart by shear. I don't think it has a 39 mph circulation any longer, but CPHC may still call it a hurricane so that people on the islands don't take it too lightly. There is still a rain threat, though that may be diminishing as well.

[Kingarabian]

New satellite, exposed center, convection dissipating - torn apart by shear. I don't think it has a 39 mph circulation any longer, but CPHC may still call it a hurricane so that people on the islands don't take it too lightly. There is still a rain threat, though that may be diminishing as well.

Hey wxman57, thank your for the updates this afternoon. Do you think Oahu is still under a rain/flood threat?

[tolakram]

25 frame visible

https://weather.msfc.nasa.gov/cgi-bin/get-goes?satellite=GOES-W%20PACUS&lat=19&lon=-158&zoom=1&width=1000&height=800&type=Animation&quality=85&info=vis&palette=ir1.pal&numframes=25&mapcolor=yellow